Abbildungen der Seite
PDF
EPUB

to admit its being laid within the shuttle. On push-
ing the point of the reel to the hole in the front end of
the shuttle, the spring forces it in and retains it.
The Singer shuttle reel is kept in place also by a
similar bolt and spring, which is inserted in a hole in
the front end of the shuttle, as represented at T, Fig.
8; the reel R rotates on centre points. The thread
passes from the reel to a slot Sin the under side of the
shuttle, then back over the reel to the top side, through
one or more holes, according to the tension required.
The threading is arranged on the same plan in the
Thomas's shuttle, represented at Figs. 9 and 10, but
the reel is square ended, and rotates in a hole in the
point end T, and a slot U; in the thick end of the
shuttle, a latch V is shown open, and is made to turn
on its centre pin into its slot W, which it fits tightly.
To hold the reel in place in the slot U a piece of watch
spring X is soldered inside the shuttle to press the
reel outward against the latch V. This spring is an
important part in the regulation of the shuttle ten-
The top holes in the shuttle admit of threading
either through 1, 3, or 5 holes, but not through 2, 4, or
6 holes; this is a defect in shuttles of this class, but
is compensated for in the Thomas's shuttle by the
spring X. Practice enables the operator to bend it
to press on the reel and thread so as to give the re-
quired tension.

sion.

The tension of the two threads requires adjust ment," and the shuttle thread can be adjusted to any degree, but the Spool thread is limited. The only objection to the shuttle is its noise-click, click at each stitch; it is a merry sound and they are wise who use it; in a good machine it does the finest and widest range of work, with the least trouble. In some machines the click, click, of the shuttle is reduced to a minimum by carrying it on its frame, instead of striking it forward and backward to slide on its bed.

A PRACTICAL MAN.

THE TELESCOPE ITS CONSTRUCTION AND
MOUNTING.

an objection, being useful work performed, which cerned in an opera glass. If the diameter of this must take power on any plan, even if the thread be pencil be greater than that of the pupil of the eye, carried around the spool. there is so much light wasted, but as long as it is "The necessity of cumbersome mechanism, which smaller than that of the pupil, the larger the object renders the machines heavy, noisy, and entirely unfit glass is, the more brilliant the image it transmits. for the use of women and for domestic purposes "is a I do not understand Mr. P's diagram, inasmuch as he mistake; instead of weighing more than a quarter of places the eye in it, about halfway between the lens an ounce, one-sixth of an ounce is the weight of a and its focal point. In reality he would see exceedingly shuttle in machines now working with great satisfac- little with his eye in such a position. tion and with greater power, at a less expenditure of I suppose that the Equatoreal mounting of force, being smaller and lighter, and with no more "H. A. C. 's" telescope (2618), p. 142, has been conparts of cumbersome mechanism than a Spool ma-structed by the maker for the latitude of his obserchine. vatory, so as to require a very trivial adjustment of the polar axis to give it the proper elevation? The first thing, then, that he will have to do, will be to assure himself that the polar and declination axes are at right angles. This he must do by means of a spirit level on the pivots of the declination axis. Then he must get the optical axis of the telescope at right angles to the decimation axis. He will effect this by inserting his transit eyepiece, setting the telescope in advance ofa star, reading the vernier of his hour circle, and then noting the instant of the star's transit over his middle wire. Now turning the whole affair half round on the polar axis, let him again reclamp the telescope a little in front of the same star, again read the vernier, and once more note the time of its passage over the middle wire; then the difference two readings of the hour circle should coincide accubetween the times of transit, and that between the rately. If not, he must correct the error, if small, by shifting the wire frame through half the interval in the eyepiece; if glaringly large, by altering the position of the telescope itself in the cradle. After this he will have to see that the verniers of his declination circle read correctly. For this purpose let him thread a star on the declination wire, and read off its declination on the circle, then turning the whole instrument round on the polar axis, again thread the star on the wire; then half the difference of the circle readings will be its index error. Should this be large, the vernier must be adjusted; but if not sufficiently, so to interfere with finding a star, it not better be left alone. Finally, once more carefully levelling the declination axis, he must make the vernier of his hour circle read XII. or XXIV., as the case may be. These instrumental adjustments being complete inter se, all he will have to do will be to set the declination circle to the declination of some known star allowing for refraction, and, if needful, the index The thick shuttle is much used for slop clothing, Tilbury Fort, in Sheridan's play of The Critic," the proper screws until the star runs along the deThat very unimaginative person, the Governor of to elevate or depress the polar axis bodily by means of error of his circle), and then as the star crosses the field, but where strength and beauty of stitch is important, the Howe is preferred for best work, the Thomas's says (in his attempt to check his daughter Tilburina's clination wire. Knowing his local time he can now for flowering toe caps of boots and for the best de-rhapsody); "the Spanish fleet thou canst not see-get the instrument into the Meridian in the way rebecause it is not yet in sight." For an analogous ferved to on p. 85, by one operation; and should he reason, I cannot proceed to quote any further from succeed in this, and in the other adjustments to printed accounts of the two big telescopes, simply which I have referred, he ought to have no difficulty because there are no accounts printed to quote from. in finding such as star as Castor, in the middle of the regret that the information I am able to afford is so day vague, but trust that our famous Musical Artificer will-like the Proctors in Doctors Commons" take the will for the deed.' Touching the "H. B."'s idea of platinising specula, I should not be hopeful that a mirror would emerge intact from the heating ordeal, at all. Mr. Purkiss, as a practical manipulator, would however be the man to test this.

The Howe, Thomas's, and Singer class of shuttles differ in their length and thickness. For machines of corresponding power doing the same kinds of work, for bootmakers, tailors, &c., the Howe shuttle takes 14in. of the needle thread to pass around it; the Thomas's from 1 to 1-16th, and the Singer 2in. The length of the Howe shuttle is 24in., Thomas's 1 7-8th inch, and Singer's 1 1-16th inch. The Howe shuttle will hold 17 yards of No. 24 cotton, Thomas's 15 yards, and Singer's 20 yards. There is a defect in thick shuttles like the Singer requiring 2in. of thread to pass around it, because this 2in. must pass and repass through the eye of the needle for each stitch made, so that for 1000 stitches per minute, the passing and repassing of the thread through the needle eye will amount to 4000in. per minute, while the Howe or Thomas's requires only 3000in. per minute. This one-third increased velocity over a thick shuttle, and through the needle eye, tends to fray or weaken the thread, so that the stitch cannot be drawn up so tightly, except by reducing the speed, or using a better and dearer quality of thread.

scription of tailors' work.

Thus the long thin shuttle has the preference; it holds its place for the best work, and has not been condemned, although much has been said about the cam movement for driving it, but why it should be condemned it is hard to make out, seeing it is exact in its movement, and allows for the working of the best

shuttle.

The advocates of the thick shuttle drive it by a crank, or eccentric, which makes the shuttle travel a longer stroke t han is required, and times or adjusts it badly for the needle thread. It not only has the long loop referred to passing around it, but it also places extra strain upon it. To sum up, it is the best contrivance for fraying, straining, and spoiling thread. It must be allowed that driving the shuttle by a crank, or an eccentric, would be an improvement over the cam if it were equally efficient. The reduction of noise fand wear would recommend it, although the difference, when the workmanship is good, is but a trifle, a well fitted cam and roller lasting for years. Some of the more recent machines, put forward as wonderful improvements, multiply the evils referred to by straining a long loop around the shuttle, and at the same time cause the needle to rise before the shuttle has passed through the needle loop, so that the thread is being scraped by the shuttle and the eye of the needle, in two places at the same time. What would a lady think of an inventor coming in to improve her sewing if, while she was pulling her thread through, he used two instruments to scrape or fray it? Thus, at the same time spoiling its appearance and making it weak. No lady would allow herself to be deceived in this simple way, but let the thing be done out of sight, in a sewing machine made to please the eye, recommended by a skilful operator, with a cunning use of words, and then the inventor is so far successful as to sell a machine not constructed on sound mechanical principles, which the purchaser will find no to improve by use, but to cause much perplexity and trouble for years.

of an ounce.

Against the use of a shuttle machine the following object ons are urged by makers of the Spool lock stitch machine:-"The shuttle stitch is used principally in large machines for heavy work. It requires both heavy and noisy machinery, as the shuttle used is about 2in. in length, and weighs more than a quarter In forming one stitch it advances its entire length through the loops, and recedes the same distance, consequently moves four inches at each stitch. The movement being reciprocating, the shuttle must be started, moved forward, and stopped, started, moved back, and stopped again at each stitch; that is, power must be applied to start the shuttle twice, stop it twice. and move it four inches at each stitch, besides the power required to drive the needle arm and other movable parts of the machine; hence the necessity of cumbersome mechanism, which renders the machines heavy, noisy, and erely unfit for the use of women and for domestic purposes. In working thin material, as the cension of the two threads requires adjustment, it is difficult to bring the lock of them in the centre of the fabric; the working of the shuttle produces the zigzag stitch.; the lines of thread lie too high above the surface of the fabric; the management of the shuttle-thread is difficult, particularly for fine work, and fine thread cannot be used successfully with it."

The first objection as to weight and motion applies equally to the feed movement of the Spool machine, and would appear more complicated if described. The stroke or travel of the feed being of an inch, while he buttle stroke is 4 inches, is not to be considered

SIR,-I believe that I can give "the-Harmonious
Blacksmith" (p. 110), in a very few lines, everything that
is at present in print with regard to the performance of
Mr. Newall's gigantic refractor; as also with respect
to that of Mr. Buckingham's. My extracts are taken
from the "Report of the Council of the Royal Astro
nomical Society," presented to the fiftieth annual
meeting on the 11th of last February. The first has
reference to the great Cooke Telescope; in speaking of
which, after describing its construction and mounting
the Report goes on to say: "Mr. Norman Lockyer,
who had an opportunity of examining and trying this
magnificent instrument shortly before is despatch to
its owner, Mr. Newall, speaks in the highest terms of
its mounting and mechanical arrangements generally;
and so far as he was able to judge of its optical per-
formance, with the low power to which the state of
the weather restricted him, he considered it to be
very promising." My second extract is briefer still,
and is made from the notice of Mr. Buckingham's
have, as yet, no definite report."
instrument; "regarding its optical performance, we

object glass to which he refers as having been com-
I may inform Mr. Frank Fothergill p. 114, that the
menced by me some time since, is still incomplete. I
have worked at it in such an extremely desultory
fashion, that I do not look forward at all hopefully
to finishing it. I do not, however, plead guilty to
sheer laziness, nor wish Mr. F. to imagine that I
should derive any gratification from the application
of the words of Tacitus to myself: Uique alios
industria ita hunc ignavia ad famam protulerat."

Mr. Fothergill's question as to the linear difference
in thickness between a spherical, speculum and one
in the form of a paraboloid, pertains to Analytical
Geometry. Should your correspondent be familiar with
the theory of axes of co-ordinates as applied to surfaces
of the second degree, he can work the matter out for
himself, but if not, it is absolutely impossible to
explain it in intelligible language.

Rigel being now practically out of sight, I cannot comply with the request of "Stella" p. 115, to see with how small an aperture the comes can be observed. I may just, however, say that the late Rev. W. R. Dawes saw it, and made a diagram of it and its primary, with a telescope of 24in. focal length and 1.6in. aperture; employing for the purpose a pancratic eyepiece and a power of 70.

[ocr errors]

the services, of such an obviously competent com-
I must congratulate "Neptune" on having secured
putor as Mr. Vivian (p. 135). Only I hope that, for
the benefit of the whole optical world, Neptune
will favour us with a detailed account of the perfor-
mance of his telescope, should he construct it from
the curves which Mr. V. makes so little of calculating.
By-the-bye, when, as a lad, I had some mixed mathe-
maties drilled into me, I used, if I remember
rightly, to be told that the rule for finding the prin-
cipal focus of an, unequally convex lens was to
divide twice the product of its radii by their sum,
As I write, I just try this on the edge of my paper
with Mr. Vivian's first lens, and can not make
2 x 137.50 x 62.51

200-01

come out 82in., or 6ft. 10in., for the

life of me. I have not taken the trouble to pursue
this very eccentric computation any farther. Er pede
Herculem, and I can faucy where I should land,
were I to go through it all. But that I consider
Herschel's formula to be open to the objection that a
slight error in the radii of the tools involves serious
consequences in the ultimate performance of the
object glasses ground on them, I should advise "Nep-
tune" to buy Herschel on the Telescope," a three-
and-sixpenny book published by A. and C. Black, and
(if he be enough of an algebraist to be able to inter-
polate) to try whether he cannot do nearly as well as
Mr. V. in working out the radii of his object glass
himself.

With regard to what Mr. Preston states on p. 136,
I would just observe that it is the size of the emergent
pencil with which we are more immediately con-

Scorpio" (2622), p. 143, may find the focus of any Hugghenian eyepiece, when he knows the foci of its formula. constituent lenses, by the following very simple lengths of the lenses which compose the eyepiece by Divide twice the product of the focal their sum, the result will be its focus. Thus, if we have a field lens of 3in focus, and an eye lens of 1,

2 × 3 × 1

4

= 1, so that a Huyghenian eyepiece so constructed would be equal to a single lens of in. focus. The division of the focal length of the object glass by that of the eyepiece gives the power of the should not only think a 3in telescope "good" which latter. Secondly, I may inform my querist that li would show the 5th Star in the trapezium of Orionis, but miraculous. 3.75in. I should put as the very smallest aperture with which it could possibly be picked up under the most favourable conceivable circumstances. An eye like that of the late Rev. W. R. Dawes, a Dallmeyer object glass, and a superb night being conjoined, this speck of light might be seen with the aperture I have assigned. Thirdly, will Scorpio refer me to the volume and page in which I stated that a 24in. telescope would not divorce stars less than 25 apart? because I have no recollection whatever of ever having made any such assertion. I think it likely that a really first class instrument of this aperture would just split a 2o pair of The application of Dallmeyer's formula stars. (which I have myself given long ago more than once in your columns), is almost too crucial a test for any instrument. Fourthly, the ordinary Huyghenian eyepiece is used indifferently with reflectors (or refractors, as is the Ramsden, or positive, eyepiece for micrometric work. Finally, I should think that the Star in the larger telescope spoken of by your correspondent, would look rather smaller with 700 than it would with 250 in the smaller one; but focal length would enter as an element into this, the image being a spurious one. Cateris paribus, the shorter the focus of our object glass the smaller the disc of a star. A FELLOW OF THE ROYAL ASTRONOMICAL SOCIETY.

ASTRONOMICAL.

SIR, Assuming that Mr. Fothergill, p. 114, is correct about Dietrichsen's Almanac," the computer of the Ephemeris therein contained, must have made some odd mistake. A planet such as Mercury or Venus may change its declination perceptibly between its time of rising and setting, so that the interval between its rising and culmination may differ from that between its passage over the Meridian and its setting: but in the case of a fixed star-and Mr. F. speaks of "a Star"-its declination practically does not vary at all. So that its diurnal path is accurately bisected by the Meridian.

I cannot give Scire Volo" (2524), p. 118, the longitude of Belfast with extreme accuracy, but he may take its time as being 6m. 383. of Sidereal time, or 6m. 378. of Mean Solar time slower than that of Glasgow, with a probable error of not more than a second.

The query of" A.H.Z." (2558) is almost meaningless without some indication of his locality. In London just now the Magnetic Needle points 19° 50' to the West of North, but this declination varies markedly

To

even in different parts of the United Kingdom. take the place, for example, I have just mentioned in my previous reply, Glasgow, the declination this year is 200 15'; while at Dover it is only 19° 10. This will serve to show how very vague any answer must of necessity be to your correspondent's question in its existing form.

With regard to the letter of "Not a F.R.A.S.," ou p. 135. I must caudidly confess that I have actually been foolish enough to apply the correction twice over: ignoring, in a very careless way, that the difference in longitude already included it. His second example is right; and mine on p. 86, only correct for the purpose of obtaining his local mean time. Obviously, whatever the Sidereal time be at his supposed station, it is at that instant 8m. 78. more at Greenwich; and as it is Greenwich Mean time we are seeking, we must take the Sidereal time at the preceding Greenwich mean noon from L.S.T. + 8m. 78. (and reduce the result to mean time) to get what we require.

There would appear to be a recent fashion, with people who have nothing else to give, to offer prizes. May I commend this to the attention of " Veritas," p. 186, and counsel him to offer an organ, telescope, fish kettle, "History of England," set of flat irons (or something equally appropriate) to any one of the readers of the ENGLISH MECHANIC, who will explain the penultimate and concluding paragraphs in his letter on the page referred to?

On the

[merged small][merged small][ocr errors][merged small][merged small][merged small][merged small][merged small][merged small][merged small][merged small][ocr errors][merged small][merged small][merged small][merged small][ocr errors][merged small][merged small][merged small][merged small][merged small][merged small][merged small][merged small][merged small][merged small]

Multiply (4.) by 3 and subtract (5.) from result.
48 x + 3y = 105
9x+3y=

39 x

Cæteris paribus, I may tell Mr. D. E. Williams, (2606), p. 142, that places on and near the Equator have the shortest dawn and twilight; and those near the Poles the longest. This arises from the fact that it is not absolutely dark until the Sun has descended 18° below the horizon; and that in latitudes where he is over head, he of course rises and sets perpendicularly; and very rapidly describes this arc of 18°. other hand, in high latitudes his path becomes more and more oblique to the horizon as we approach the Poles, and he is a long time before he attains a depth of 18 below it; the ultimate result being that, even in England, at one season of the year, he never descends so deeply as this, and consequently there is no real night; and that as we come still nearer the poles, we arrive at a parallel of latitude on and beyond which, for half the year, the Sun does not set at all. If Mr. Williams has access to an ordinary terrestrial Globe, and will merely stick a white disc of paper on any part of the Ecliptic he pleases, and elevate the Pole of the Globe to various heights, be will be able to see the reason of all this at a glance. To imitate the condition of things on the Equator, all he will have to do, Thus will be to place the axis of the Globe parallel with the wooden horizon, then turning the Globe on such axis, he will see his piece of paper rise and set perpendicularly. If now he will elevate the axis until it is perpendicular to the horizon, he will observe that his white paper sun will travel round and round paralle. to it: of course at intermediate inclinations, describing paths of greater or less obliquity. We may find out, to select a familar example, the time during which twilight lasts in London all night long, by considering that the Latitude of that City is 51° 30', or in other words that the Pole is elevated at that angle to the horizon then, adding 18° to this we get 69° 30'. But from May 23rd until July 20th, the Sun's North Polar Distance is always less than this. So even at midnight, when he is due North, he is less than 18° below the horizon, and consequently there can be no real night. Any common work on Astronomy will give Mr. Williams further details on this subject.

A FELLOW OF THE ROYAL ASTRONOMICAL SOCIETY.

EARTH'S ROTATION.

SIR," C. R. O., Hants," adopts a mode of discussing centrifugal at tendencies which is a favourite one of my own in all such matters. It is so simple and In all such questions, one clear as to be worth notin has only to consider wat is the change of direction effected in a given time on a body moving with a known velocity to estimate what force has been called into action. By this simple principle I was able in my "Saturn" to weigh Saturn against the earth (by considering motion of his satellite Titan) without even having occasion for an illustrative diagram. The principle is very fertile.

I present my compliments to "C. R. O., Hants," on the lucidity of his reasoning.

RICHD. A. PROCTOR.

FIGURE OF THE EARTH.

SIR, Mr. Beardsley is an apt pupil of " Parallax," and will soon quote others to his purpose as cleverly as his teacher. He quotes me as saying the earth's rotation can be proved by the simple fact that a rotating semicircle may be made to keep pace with the sun. I said nothing of the sort. He quotes me as making a certain remark about Tycho Brahe's system. I wade no such remark. Paradoxists may be divided into two great classe1. I know now to which Mr. B. belongs.

What I really said of the experiment referred to was that it proved that if the sun move, his motion is of a certain character; what I said about Tycho Brahe referred, as B. knows, to the subject of the earth's revolution, not to her rotation.

"W. H. L." wants me to argue with Beardsley. With thanks, I decline. Mr. Dyer must be a very young man not to know that Parallax and Co., are merely types of a class which will always exist. Suppose "Parallax " does "unsettle the minds of many people who have not studied the subject." What then? It serves them right for leaving the subject unstudied. They have been settled in ignorance, and Parallax " is unconsciously doing capital work by unsettling them. More power to him! RICHD. A. PROCTOR.

P.S.-In the hope of encouraging Beardsley to grow into another Parallax," I invite him to screw up his courage, and invent a reason why the sun, supposing it to set, as shown in his Fig. 3, (borrowed from" Parallax)," does not seem to vary in size, with those awkwardly varying distances. He might extend his proof to the general solar motions as conceived by his teacher.

[ocr errors]

27

=

78

78

[ocr errors][merged small][merged small][merged small]
[blocks in formation]

18 = 9

18

+ 3y = 27

3y = £7

9

= 3

3

9

[merged small][merged small][merged small][merged small][ocr errors][merged small]
[blocks in formation]

3y+22=

8- 9

II. (1.) 5 x

[blocks in formation]
[merged small][merged small][ocr errors]
[blocks in formation]

BLUE MAHOE WOOD FOR FISHING RODS. SIR, Our friend "The Harmonious Blacksmith," p. 111, last number but one, wishes some information about blue mahoe wood, which he says is excellent for making fishing rods. He asks also where he could purchase it. I made some inquiries about the origin of that wood, and hope the following particulars may enable him to obtain it.

The name of mahee or mahot is given to several plants, especially to different fibre-yielding Hibiscus, also to some Lecythis and Dombeya. Mountain Mahoe (Hibiscus elatus) is 50ft. high; a shingle of that wood coming from Jamaica, was exhibited in London, 1862, and said to last 6 years without any paint. Seaside Mahoe is Hibiscus tiliaceus, of which there is a white and also a blue variety; it is, I believe, 6ft. to Sft. high; its name in Panama is Mayagua de la playa. Now, I find in a catalogue of MM. Fauntleroy and Co., (actual firm. Mundy, Horley and Co., 100, Bunhillrow, E.C.) the "Mayagua azul wcod," and this will be, I believe, the "blue mahee"; having no sample I cannot further examine it, but it will be easy for "the H. B." to apply to that firm, and I shall be happy if I have obliged him who has obliged so many brother readers. BERNARDIN,

15) Multiply (1.) and (2.) by 3 and 4 respec- AN ENGLISH MECHANIC MUTUAL IMPROVE

19tively, adding the re-
19)sults we get (4.)

Then multiply (1.)
and (3.) by 6 and 4
(3.) 2x + y + 6 = 462 respectively, subtract-
ingthe results, we get
(5.)

[merged small][merged small][merged small][merged small][merged small][merged small][merged small][merged small][merged small][merged small][merged small][merged small][merged small][merged small][merged small][merged small][merged small][merged small][merged small][merged small][merged small][merged small][merged small][merged small][merged small][merged small][merged small][merged small][ocr errors][merged small][merged small][merged small][merged small]

MENT SOCIETY FOR BLACKBURN.

SIR, AS I feel certain there must be many subscribers to your excellent journal in Blackburn, I beg to suggest that a few of them who know each other should meet together, and arrange to have a meeting such as our Edinburgh and Manchester brethren have resolved upon. No doubt we could muster a goodly number, and help on this new intellectual project; for encouraging the arts and sciences.

J. HARRISON MORAN, 2, Brook-st., Eanam, Blackburn.

SALADS.

SIR,-Permit me to draw attention to the value of dandelion leaves as a salad. Although much used abroad, the plant is little appreciated here, as indeed Multiply (4) by many others that might enter into our dietaries. At this season of the year, salads constitute valuable articles of diet. They are recommended not only on account of their cooling and refreshing taste, but chiefly from their containing mineral matters, which are so essential to the maintenance of health. These mineral matters consist principally of salts of potassium and sodium. When vegetables are boiled, a certain portion of their mineral constituents is extracted by the water, and hence the practice of eating uncooked vegetables and fruit is a most wholesome one, as furnishing the system with saline matters, which are much needed. The following plants are used as salads in this country:-beer, celery, endive, garden To this list cress, lettuce, radish, and water cress. might be judiciously added the leaves of the dandelion, Lamb's lettuce, or ¡corn-salad, sorrel, aud many other wild plants, which through ignorance or prejudice are at present despised.

419

11 x

20 y =

47

33

20 y =

47

47

33 =

[blocks in formation]

20 y = 80

80

[blocks in formation]

8818

[merged small][ocr errors][merged small][merged small][merged small][merged small][merged small][merged small][merged small][merged small][merged small]

SIR. I believe "C. H. W., B." p. 131, No. 266, has not given the complete solution of the 2nd equation, an equation of the nth degree having n roots, we have the two equations (a) 1 o, and (b) x + 32, or +25= 0. - 1 = (x (a) x3 Which gives x-1= 0, x = 1, and 24 + x3 + x2 + x + 1 = 0, Reciprocal equation, dividing by

[merged small][merged small][merged small][merged small][merged small][merged small][merged small][ocr errors][ocr errors][merged small][merged small][merged small][merged small][ocr errors][merged small][ocr errors][ocr errors][merged small][merged small][merged small][merged small][merged small]
[ocr errors][merged small][merged small]

SIR,-In reply to "St. George," I inform him that it is not a new plan of case hardening, although it was not generally known. I have used it for years, with only this difference, that I put about one-third of salt among the prussiate of potash, either in a retort or on the red-hot iron at the smith's fire, and by re-heating and giving it another dose it will be better. ,I case hardened some things about two years ago for experiment, and dipped them in a mixture of one-third of sulphuric acid among the water with good results. Everyone was surprised that saw them, and so was HEATHEN JACK.

SCREW CHUCK.

If

SIR,-I have been looking for a reply from Marine," in answer to "J. K. P.," who says he is in error in saying that "A. B." put a left-handed screw on his chuck. He says: "I know a machine with a screw on each end, the one right, the other left." "J. K. P." saw a machine any other way it was wrong; for if the back centre is screwed in the spindle, it must be a left-hand thread. In the same number (262) "J. K. P." gives a drawing of Bennett's chuck. The thread is put on right-handed, and it is If "Marine the reverse of that of "A. B." was in error, how are they not both the same? HEATHEN JACK.

"

May the "Blacksmith" take the liberty of cautioning "Joe" and others against being taken in by any of that old nonsense about rods weighing an ounce, or

thick.

ANCIENT ARCHITECTURAL REMAINS IN INDIA. SIR,-Probably there are very few places on the earth's surface where ancient civilisation and barba-less, per foot of their length? He has seen a roach rod 22ft. long, weighing only 21oz., and its action was rism have co-existed side by side, as it were, to an very good without its butt. extent equal to which has prevailed in what now conThis remarkably small stitutes the British dominion in India. At a remote weight was obtained by boring out its butt-made of period our Aryan ancestors conquered this country, shaved jungle bamboo cane-until it was less than fin. but of course their conquest was not a perfect one (no Need he add that it was soon split to pieces. conquests ever are, excepting those domestic conquests boo-was substituted for it, the rod became faultless; When a suitable butt joint-made of East India bamachieved by wives over husbands), and the Aryan but then it weighed a few ounces more. No doubt it conquerors became to a considerable extent amalgamated with the more ancient populations, which was weighed heavier in its bag, but it did not feel heavier probably the origin of the complex system of castes in the hand when in use, for the very simple reason that the additional weight was at that end nearest the which grew up, the pure races, as the Brahmins and the warrior caste, remaining the governing classes, as, augler. A very slight weight added to its top would indeed, soldiers and priests, when united, almost in-heavy to lift out of the water with a long rod. have been much more felt, just as a small fish feels variably do, "even until this day.”

THE FUEL OF THE SUN.

long time ago," and never has, nor ever will, cool
down to the temperature of a member of the "tem-
perance association of planets," if such a oody be, I
have not included either him or his four moons among
those bodies which I suggested may have been pro-
jected from our sun in the olden time. If, as he sup-
poses, the surface of Jupiter is now as hot as melted
platinum, and will never become cooler, I cannot
help thinking that this great bomb, compared to which
discharged from Mallet's mortar, mere grains of sand,
the asteroids are as sparrow shot, and the projectiles
must have been in a state of mere gas when projected,
if it ever were projected, from the sun, and gas, per-
haps rarer than hydrogen, could hardly have held
together, and however much condensed during its tra-
jectory, been shot so far as Jupiter is from the sun.
Mr. Williams also thinks that Jupiter, Saturn, Uranus,
and Neptune, and the planets, if any, yet more dis-
tant, have photospheres, and that none of the planets
originally had atmospheres, but have "picked them
up "by attracting aqueous vapour, &c., from inter-
planetary space, just as I have supposed they picked
liquid surroundings, whether in the form of atmos-
up their attendant satellites. That their aerial and
pheres or oceans, have been derived from without or
from within, is certainly a very interesting specula-
Hibernian philosopher termed a very abundant lack
tion, but one, I fear, of which there is what the
of data from which to estimate the probabilities of
either hypothesis.
THE HARMONIOUS BLACKSMITH.

THE BOOMERANG.

In India the conquering race, to a considerable extent, adopted the superstitions of those they subd ed. Modern Hinduism is anything but the pure theism of the ancient Aryans, as Baboo Keshub Chunder Sen would tell SIR,-Under this title a fellow blacksmith, who has us; and some of those ancient populations seem not rather more science than the ignoramus who writes much, if any, further advanced in civilisation now than this, bas produced an interesting work based on the they were thousands of years ago, when the lighter-hypothesis that all interplanetary and stellar space is coloured Aryans conquered them. Nevertheless, they occupied with matter identical with that found on have in many instances re-occupied their lost ground, earth, and that the sun, in his journey through space, from which the higher race has retired, although they do is continually attracting it to himself, at a rate probably not seem to have improved the occasion," and copied exceeding 160 millions of millions of tons per second of the example of those who temporarily occupied, say, time, and leaving behind him a proportionate quanthe site of the city of Mandoo, whose architectural tity of what the author, borrowing an idea from his works would do honour to Greek and Roman civilisa-smithy experiences, terms exhausted fuel. This hytion, if, indeed, their remains do not surpass any of pothesis appears to have the advantage of accounting the works of those peoples, except in statuary. The for observed facts without requiring us to admit the ground on which the remains of this ancient city existence of any unknown causes or new forces, exSIR, I herewith beg to enclose a sketch of a small Stand is now occupied by the savage tribe of Bheels, cepting the assumption that the matter diffused boomerang, which I made myself after an original who are not only incapable of mason's work, but are through space is identical with that with which we are model. I can throw it perfectly, and do so in the 100 barbarous to build even a comfortable hut to shel- familiar, which seems at least very probable, although following manner-viz., I catch a firm grip of the long ter them, or to cultivate the earth for their subsistence, of course we must not assume that we are acquainted side near the point with the two forefingers and and, like the Santhals, they are yet only armed with with all kinds of matter which may exist in the stars, thumb of the right hand, holding the inside edge bows and arrows, a most convincing proof of a low the sun, in other planets, or even our own, seeing that direct towards the ground. I aim at an imaginary state, for there can be no doubt whatever that gun- we are not acquainted with its interior. powder and the gallows are the most salient signs of Mr. Williams thinks the temperature at the lower object about 30 yards off, fetching the boomerang over the shoulder and flinging with a straight, smart civilisation. THE HARMONIOUS BLACKSMITH. strata of the sun's atmosphere is rendered so high-throw, as if I wished to stick the point in the ground probably far higher than the melting point of plati- at the 30 yards' distar ce. It goes to the object straight, num-by that condensation which results from the then gradually rising to a height of from 80 to 100ft., great pressure due to the attraction of so large a mass; sweeps away to the left, and comes down in a that the elements of water, and probably all terrestrial compounds, become dissociated, and that those elements from time to time rise into the higher regions of the sun's atmosphere, again to combine, with explosions compared with which our gunpowder and nitro-glycerine go off mildly. It is this re-combination of the constituents of water, accompanied by that evolution of light and heat which we term combustion, from which he thinks most of the sun's heat and light which we experience is derived, and I do hope "F.R.A.S.," Mr. Proctor, "Sigma," and other physiciens, who, of course, know all about the sun's fuel, and everything else, will favour the unlearned blacksmith with their opinions on Mr. Williams's theory.

SHEATHING IRON SHIPS WITH WOOD AND
COPPER.

SIR, I did not intend to assert that the Admiralty
had definitely adopted a modification of the plan for
doing this which I designed about 1861, but only that
they had adopted it experimentally-in the fast frigate
Inconstant, if I am not mistakeu. In my design there
was no difficulty in obtaining a perfect adherence of
the wood, for it was contined in dovetailed iron
grooves formed by affixing angle iron to the ship's
outer skin, and driving the wood into the grooves so
formed. If I remember correctly, asphalted felt was
introduced between the iron skin of the ship and the
wooden sheathing, so as to form a water-tight joint,
and prevent the injurious action of sea water on iron
in contact with wood. I am almost certain I have the
coloured drawings of this design by me, and if you
think, Mr. Editor, the matter of sufficient importance
for a small engraved illustration, I will look them up
and send them to you. In regard to its importance 1
may remark that could mine or some similar plan be
carried out without too great expense, iron ships
might not only be employed as cruisers on stations
where there is no dock accommodation for large war
ships, but in such services as the Southern whale
fishery, in which a ship often remains undocked for
three successive years, and unless sheathed with cop-
per would become the local habitation of the great
Barnacle family to an extent undreamed of even by
Charles Dickens himself.
THE HARMONIOUS BLACKSMITH.

A SOFT-VOICED PIPE FOR A CHAMBER
ORGAN-FOG-HORNS.

SIR. At the southern extremity of the Isle of Wight an experimental fog-horn has been erected, which is voiced exactly by the same means that are employed to voice the reed pipe of an organ; but those means are on rather a larger scale. The steel reed of this trumpet pipe is five inches long by two inches wide, and is put in motion by air at the pressure of about 101b. to the superficial inch. How many inches of water this is equivalent to I leave "Adept " and Mr. Kemble to "kalkalate." This wee pipe, or chaunter. as a cannie Scot would term it, can hardly discourse sweet music, but its sound, A, second space in the tre

even Princess Alexandra of the ENGLISH MECHANIC ble, muust, I think, be sufficiently strident" to satisfy herself; for I am told it can be heard many miles out at sea, when other sounds are so difficult to transmit

through fogs.

A lifeboat is a very good thing, and I trust we English Mechanics will, ere long, add at least one more to the number of those which are stationed on our rockbound coast. But however desirable it is to save the lives of shipwrecked men, it is yet more desirable to prevent shipwreck; so I do hope this born may long remain exalted, and, as Sam Slick would have said, its sound continue to be a caution to mariners, warring poor Jack of the dangers of too near an approach to land in foggy weather.

THE HARMONIOUS BLACKSMITH.

BLUE MAHOE WOOD. SIR," The Harmonious Blacksmith" respectfully informs "Joe "that he, the said Vulcanite, is not in the market for fly rods, nor indeed anything else at prepresent, excepting it be ancient and rare musical instruments, and that he has no intention of entering the market, for fear he should himself be "sold. Banter apart, he cannot inform "Joe" the weight of his long three-joint North Carolina cane fly-rod, simply because it is not now in his possession, and can only say, in general terms, that it was extremely light, and did not fatigue the user much more than a rather powerful 12ft. hickory rod would do, and that he knows no solid wood which would not be very much heavier than bamboo.

Mr. Williams is of opinion that the solid, or more
probably fluid, nucleus of the sun is comparatively a
small body, whose position, in relation to the common
centre of gravity of the solar system, is to a great
extent influenced by the planets, and that to its somie-
what irregular fluctuations within its atmosphere may
be due some of those more violent explosions which
he thinks project matter far above its visible limit.
To such projected matter he refers the cause of the
zodiacal light, and probably also the asteroids. He
sees no specific difference between large and small
particles, and thinks that meteorolites and asteroids
are simply larger and smaller specimens of the suu's
projectiles, differing from each other only as small
shot differs from cannon balls. If this hypothesis be
reasonable, I can see no objection to its extension to
the formation of all the smaller planets, say to Mars.
For anything I can see to the contrary, the earth and
all the rest, as far as Mars, differ from asteroids only
common parent, the sun, during one or more of his ex-
in size, and may have been thrown off from
plosions-I hope not of ill-temper, although he is said
to be rather hot. Chemically, meteorolites and our
planet resemble Cæsar and Pompey in being "berry
much alike," and perhaps the latter are only the big
brothers of the former, for difference of size no more
includes difference of genus that the huge magnitude
prevent both from being pachyderms.
of the elephant and the minuteness of a sucking pig

Our

Perhaps Mr. Williams-in deference to the feelings
of his weaker scientific brethren-feels the necessity
of drawing the line" somewhere, so, for the present,
the smaller planets and our satellite, I can't guess. In
he draws it at Asteroids; why he should not include
a recent number of the ENGLISH MECHANIC, it is
reported that Venus has lately had a baby (query, Vas
its cradle the observer's telescope?)-1 mean a satellite
-now if the sun has been for ages projecting meteoro-
lites and asteroids, until the interplanetary spaces are
thronged with them, it seems no more than reason-
able that Venus may have picked up one, and, like a
Considering the great
charitable female, adopted it.
distance her husband Mars has been from her during
all historic times, this seems a more charitable hypo-
thesis than that her satellite is her own production,
and as charity is said to cover a multitude of sins, I
hope my charitable suggestion may cover some of these
manifold sins which, according to Mr. Herman Sloman,
I have committed in the pages of our journal.
If the earth has picked up her moon in times past,
and Venus lately adopted a little waif, which was
sadly wanting maternal care, may not all the planets
within the orbit of Jupiter have done the same, and
really have attendant trains of satellites from the size
of the smallest meteorolite to that of a small moon, of
whose existence we are ignorant, only because they
are too small to reflect enough of the sun's light to
make them visible in our best telescopes? And may
not some of them occasionally become luminous when
they enter our atmosphere? I've no very great dith-
culty in supposing the possibility of this, but that may
be due to my crass ignorance.

INS

circle and alights within a few yards of where I throw
it from, generally behind my back. I find it does its
work better when thrown against the wind, which
should never be more than a breath. Mine is made of
apple tree, but I fancy any tough hard wood would
do, provided the grain runs parallel with the bend.
This is necessary, for if the grain of the wood runs
across, or through the bend, the boomerang suaps in
that spot when it hits a stone or other hard object. I
have made three or four now without any difficulty
except that of getting the grain right. They have all
broken at the bend owing to the straight grain. One
I have used for two summers, came to grief last week.
Anyone wanting further information will have it, and
welcome, by applying through our unique journal.
It is in. thick, tapered on all sides to fine but thick
edge.
VIVIS SPERANDUM,

HYPOCHLORIC ACID, &c.

SIR, I see week after week that your paper is filled with valuable matter, therefore, absurd arguments are best omitted As to my communication respecting hypochloric acid, I shall not argue-the acid does not exist, although caustic alkalies absorb chlorine tetroxide. This latter was termed by Liebeg, in his "Elements," chlorous acid.

My tardiness in replying to "U," in your impression of the 8th, has been caused by my undertaking a could go in separating barium chlorate from the series of experiments to determine how far I really chloride, and the result was that when operating with quantities calculated to produce 304 grms, of the chlorate I was able to separate 267 grms. of this salt. I shall not give the full particulars unless specially required to do so, as it would be only taking up the space of your valuable journal.

If querists would only be more exact in stating what they require, and in many cases the purpose for which the article is required, they might cften be answered in a very few words. For instance, in the barium chlorate question, if the pure article was wanted, why not have said so? However, I have, in spite of our old correspondent under a new face, quite satisfied myself that the pure article may be obtained by my method, and in spite of the bold assertion made by the correspondent alluded to, the alkaline chlorates are easily separated from the chloride.

If such separations as these were the only operations of a laboratory, practical chemistry must indeed be an easy science; but good instances of separations are not to be found in such single instances as the one just illustrated, the difficulty increases almost to perplexity when we have to separate bodies of complex structure formed by the obscure action of reagents upon bodies of organic origin.

[ocr errors]
[ocr errors]

GEORGE E. DAVIS. Errata in article on Symbols," col. 3, p. 98, for Ca read Ca" O. Col. 1, p. 99 three errors occur As Mr. Williams thinks Jupiter is a sort of miniature H,') sun, which our sun has picked up in his journey in the formula; for tetrethyl ammonium hydrate, through space, "in the days when he went gipsying a platosammonium chloride and ethyl aldehyde.

H2

MAY 6, 1870.]

BREWING.

gra-Having seen from time to time many inquiries in your pages relative to brewing without ellelting a reply, am induced to send you (another brick) for insertion, if you think desirable, the following:

Mach mystery is made about the art of brewing-it is an art easily understood-any one who can make tea can make ale or beer, the process being exactly similar. Put a handful of ground malt into a teapot, fill with water nearly boiling, mix, let stand for some time, pour off the liquor, add a few hops, and boil till the wort breaks-that is, comes up in large flakesthen draw off to cool; when it has cooled to about 65° to 70° add yeast to ferment it, and the beer is made. The above is the whole art of beer making, either on a large or small scale, and as many of your readers may like to try their hand at it, I will proceed to details. First, utensils: these in a small way should consist of a copper to hold, say 10 gals, a tub, an oar, a sieve, funnel and tap, a tub for cooling, and 2 9 gal. casks. Take 1 bushel of malt gronud fine, place in the mash tub, then add 2 gals. of water at 1820 of the thermometer (not having one, if it is sufficiently hot to bite the finger it will do), mix up well with the oar, so that it may be well wetted-if the water is too hot it will set the malt and prevent it breaking-aften. well mashing cover over with a sack, so as to hold the heat. When this, the wort, has stood one hour and a half, try your liquor; if it runs clear it is ready for boiling, if not claar put back again, and let it remain till clear, then draw off into your cooling tub preparatory to boiling. In the meanwhile have ready a second 10 gals. of water ready to pour into the mash tub upon the drained malt at a temperature of 190°, well mash and let stand one hour, then draw off if clear and proceed to the boiling. You take the first wort already drawn off, place it in the copper, adding 1lb. of hops and a small quantity of salt, make boil, and considerable attention should be paid that only a gentle ebullition be kept up; after boiling about an hour and a half, flakes will begin to come up, and when they come up somewhat large will be time to draw off to cool, and here it is that written instructions fail-experientia doces. If not boiled enough the beer is apt to taste raw and sickly, if too much it will thicken, and never be agreeable to the palate; when boiled enough, strain through the sieve into the cooler to cool to about 64°. Then take the second mashing and boil in a like manner, adding 1lb. fresh hopsthe old ones will not do-for, say one hour, then draw off to cool, and you can add the two worts together, if so inclined, when at the same temperature-don't add the hot to the cold-to ferment together or separately, in either case you add one pint new yeast to each 9 gals. of liquor, stirred well in, set aside to work for two days, this is best done by-having placed the beer in barrels-filling up the barrels as they work over with beer retained for that purposein a week or so it will be ready for use. The above is brewing pure and simple, and I trust it will be found useful. Many an artisan could at all times ensure himself a glass of good wholesome beer at one-half the cost he pays for the vile trash now purchased at the public-the trouble is not much when once the mill is set a going if he will only have

a little

PATIENCE AND PERSEVERANCE,

METRONOME.

This is effected by four cam wheels C, C, C, C. of equal
size, but having respectively 8, 12, 16, and 24 teeth;
which wheels are fixed on the same axis as the impulse
To illustrate their action, I will take that of
wheel.
the cam of 12. Suppose the slider be set to 144 beats
on the scale of the instrument, these will take place in
one minute, and 72 teeth of the impulse wheel will be
concerned in their production; or, in other words, the

[blocks in formation]

wheel, having only 24 teeth, will just make 3 revolu tions. The cam of 12 being on the same axis will, of course, turn at the same rate; and if its teeth be allowed to lift the hammer tail shown at H, 36 blows will be struck on the bell for every 144 swings of the rod. This proportion of one chime to every 4 beats or swings will remain constant for any number the slider may be placed at; but the hammer is mounted on a slide, and can be brought into action with either of the other cams, when the proportion will be different, SIR,-I here furnish, in answer to query 2408, a and every second, third, or sixth beat may be chimed; ketch of this instrument unencumbered with the or the hammer may be slid out of action altogether, framework, in order to more clearly show its essen- the slide on which it is fixed terminating in a push tial ports. B is the mainspring barrel, its wheel of piece outside the wooden case. 120 gearing into a pinion P of 10. Upon the axis of The instrument is easily stopped, if desired, by This latter, nearest the barrel, is a wheel W of 24, the restraining the rod R in the position shown in the teeth of which are of peculiar shape, so as, through an figure, when the impulse wheel is opposed by the plain intervening contrivance, to give vibrating movement part of one of the discs. To prevent overwinding, to the rod R. To explain this, I have made the sepa- there is a stop-work limiting the winding to 5 turns, rate sketch of this part enlarged. The object involved and of course the barrel arbor has a ratchet and click. is that of converting the continuous motion of the The instrument which I make this description from wheel in one direction into that of an alternate is by Paquet, of Paris, and made according to Maelzel, vibrating one at right angle to it; and if the action who invented the metronome in 1815. as not already figured in the excellent plates of "Mechanical Movements," it is well worthy of description in the ENGLISH MECHANIC. The wheel teeth are very slightly undercut, and are square, but with their acting front so bevelled as to be wedge-shaped, their middle pins standing prominent. They are at intervals of about two teeth from each other. Upon an arbor placed transversely to the wheel are fixed two Snail-shaped discs DD, at such distance apart as to just have shake between any two teeth of the wheel, which in turning may embrace them, and also to allow of similar shake when either of the teeth is between them. The discs are of equal size, but reversed in position, so that their acting slopes S, which are bevelled from behind, may stand in a line with each other.

Suppose now the mainspring is wound up, the front of a tooth of the impulse wheel will press against the sloping edge of the back disc and move it aside, to the right, until the tooth escapes from it and drops on to the slope of the front disc, which it also drives aside, but in the contrary direction, until the tooth finally escapes. A like action is caused by the succeeding teeth, the rate of their escape being governed by the position of a flattish weight or slider A, held friction tight on the rod by a spring clip, as shown in the figure; for the rod is fixed on the same axis as the discs, moves with them to either hand,'and, in fact, is a pendulum, whose rate of vibration is controlled by shifting its centre of oscillation by means of the slider on the upward continuation of the rod, To dilate further upon this would require more space than the present communication warrants; suffice it to say that the frequency of the vibrations and their accompanying audible beats (the latter caused by the drop of teeth on the dead part of the discs, but intensified by the resonance of the wooden case) can thus be varied from 40 to 208 per minute. The much heavier lower weight F is to balance the slider, and by its momentum the discs are carried further than necessary for the mere escape of the wheel, so that the latter does not at once drop from the slope of one disc on to that of the other.

The part remaining to be described is that for striking the recurrence of stronger accents on a bell,

H. H. L., Manchester.

ROTATION OF THE EARTH, &c.

SIR, I have lived long enough to feel convinced that under the head of "Original and Independent Thought" a great deal of original and independent nonsense is uttered; but I cannot help acknowledging that if the hearers of Parallax" and charlatans choose to believe the rubbishing theories of those gentlemen," they are perfectly at liberty to do so. If individuals supposed to be sane choose to accept the theories of these "gentlemen," by all means let them. If they cannot ask themselves the simple question "What advantage do Mr. Proctor and the other astronomers gain by telling these lies," ("fraud and falsehood" are the choice expletives Mr. J. Hampden uses), let them remain in their ignorance. Burning the candle to give them light is waste of time, life (for life is not too long), and money. But I agree with you that it is not advisable to smother Mr. Beardsley's letters; let them have the light of day by all means. By the way, I should like him to explain the following fact:-Last winter, while an unmistakable East wind was blowing on the surface of the earth, I saw dense clouds travelling from S. W. to N.E. cross the moon at the rate of 10 miles an hour. How does Mr. B account for this?

With regard to Mr. B's. little "difficulty" about a strong south wind infringing on the peaks of the earth, p. 90, he need not be alarmed. It would have about as much effect as Mr. B. could produce by blowing with all his might against the side of a cog wheel in rapid motion. Mr. B. does not say anything about the extent of surface on which this strong south wind is to blow. I imagine it would have to be a very broad "belt" indeed to induce the peaks of the Himalayas to deviate from the path they describe.

Does not Mr. B. think it would be advisable to give us his own theory instead of picking imaginary holes in the received explanations of mundane phenomena ? Of course so learned and talented an inquirer into the mysteries of Nature has not adopted his theories without laborious and painstaking research, and has arrived at a solution of the various "difficulties"

[blocks in formation]

COMMERCE AND TRADE. SIR,-As "our" journal is the only one that circulates in every workshop and amongst all classes of workmen, I should like, with your permission, to elicit some opinions on the above subject. To make the matter plain, I will put the question in the form of a short extract from the "Statesman's Year-book for 1870":

"The sum of the imports into the United Kingdom for the year 1868 was £291,693,608. Meanwhile the exports for the year 1868 amounted in all to, £179,677,812. We are exporting less, and importing more. The question arises, What sort of prosperity' does this indicate?"

"

I venture to think the answers to this question will be of very great interest to a majority of our readers and certainly no journal has a better opportunity of eliciting useful information on this important subject than the ENGLISH MECHANIC. Of course politics are tabooed, as well as theology, or our happy family" cage will become a den of roaring lions.' SAUL RYMEA.

[ocr errors]

A LIBEL ON BRITISH WORKMEN. SIR, I wish to call the attention of English mechanics to the following extract from a leader in the Globe of April 20. The writer says:-"Our notions of education are somewhat crude and superficial, and we are a trifle too proud of our barbarous alphabet and our imperfect multiplication table. Those men whose work is visible in Westminster Abbey spoke better English than ours, although they were unable to write it; and their education, being moral as well as intellectual, caused them to do good sound work, instead of scamping 'everything in the modern fashion. They loved their work, whilst too many of our modern artisans hate theirs. Why they do so is a wide question. It is not wholly their own fault; it is the vice of an age in which betting men and stockbrokers are the very cream of society (!) The men who built our cathedrals had a share in the structure as complete as the architects. But the workmen of to-day are very much like other fungous growths of the time. They care for what their work will produce, not for the work itself. The thing now deemed desirable to be learned is how to make the most money with the least expenditure of labour."

Now this is a deliberate and unjustifiable libel, for if the writer had really any knowledge of the matter on which he writes, and of the world in which he lives, he would have heard of a writer named John Ruskin, and if he had read his works he would have known that it is mainly through the system of paying by the piece that so much of the work of the present day is "scamped." To say that "everything" is for although there are doubtless hundreds of houses "scamped" is to say that which is notoriously untrue; "run up," that is no proof that "good sound work" is not put into hundreds of others; and I have not the slightest doubt but that Mr. G. G. Scott knows where to find masous and sculptors in every way worthy to To say that the men who built Westminster Abbey spoke better English than we do, and that they did better work because their education was "moral as well as intellectual" does not say much for the advance of civilisation" or the "power of the penny press." If their language was so much "better" than ours, why does not the Globe adopt it?-possibly it might increase its very limited circulation. It is no palliation of the Globe's offence to say that it is not

build another" Westminster "or another "St. Paul's."

wholly the fault" of the workmen; for anyone who looks down the list of tenders offered for any large building will see that in 9 cases out of 10 the "lowest tender" is accepted, although it is very likely less than half the amount of the highest. So long as "consumers of labour" adopt these tactics, so long will builders use interior material and inferior workmanship. It is simply nonsense to say that the workmen of to-day care merely for what their work will produce." I can go and buy an inferior watch at a low price; and I can also get a "good sound" article at a fair price. The labourer is always worthy of his hire; and it would be ridiculous to charge the watchmaker who asks a "good" price for the produce of his labour with liking his work only for what it will produce., The same argument applies to all the relations of lite, and one number of the ENGLISH MECHANIC gives the "lie direct" to the assertions of the Globe; for there "he who runs may read" that men do love their work for their work's sake. The sentence about speaking "better English" shows the amount of knowledge of the whole subject possessed by the Globe. seeing that the men who built and rebuilt the extant West Minster lived at intervals between 1221 and 1809. (The foundation stone of the present building was laid by Henry III., in 1221, since which time it has been "added to" up to the reign of Henry VII. Portions have been re-built so late as 1809.) But possibly the best reply to such ridiculous

bunkum" is furnished by an earlier sentence in the very "leading article" from which I quote. "Such nonsense is not worth serious criticism, indeed, it is easily explicable from the fact that Easter is a holiday for journalists as well as politicians, and that newspapers must be filled, even though the better brains of the establishment are away in the country." It is a great pity the writer in the Globe could not see that a "pen "is a weapon that "stabs" both ways. Certainly the "better brains" were absent on this occasion. SAUL RYMEA.

CHICORY AND STARCH.

SIR, From unavoidable circumstances, partly connected with the business of this time of the year, I

have been unable to pen down the article on starch; but such as it is I now send it to you. In the number before last of our MECHANIC, there is an article from the Food Journal in which it states that chicory is procured from the endive root. Is not this a mistake? The root of the Cichorium intibus, L. has been used for that purpose, and I should have thought the endive would not have been likely to be used in preference to chicory plant. There are several substances having the name of starch, and which chemists tell us are closely related to each other in chemical composition, -namely, Iceland moss starch, fichen starch, lichenin, found in Iceland moss and other lichens: animal starch, found in the liver and placenta; inulien, found in the root of the clecampane, dahlia, and Jerusalem artichoke; and the ordinary starch as we find it in rice, &c. This latter substance is that which forms the subject of the present article. Starch occurs in the form of grains of very various shapes and sizes, occurring in the cells of various parts of plants, most frequently in the seeds, roots, and stems, and also said to occur in the receptacles and pollea of flowers. These grains resemble each other in one particular, - namely, a point which, from its shape and position, is often characteristic of the kind of grain to which it belongs. In viewing starch under the microscope, as they lie in their containing cells, I think it is impossible to avoid the conclusion that this point is the point of attachment of the grain, and forms the nucleus around which the starch grain forms; for all the parts of the grain are related to it. Starch, under the microscope, usually presents the appearance of partial or complete curves surrounding or related to the above point, or hilum, as it is called; indeed, it would appear as if the grain consisted of a number of coatings, their common meeting point being the hilum. This structure is rendered more apparent in the following experiment:-Place a little arrowroot or potato starch on a glass slip with a little water, add a minute quantity of tincture of iodine, let it be a few seconds, then soak up the moisture with a small piece of blotting paper; place a thin cover of glass over the starch left on the slip, place on the microscope stage-a power of in. focus will do very well; just drop a little strong sulphuric acid carefully by the edge of the glass cover so as to let it run between the two glasses, and cover the starch. The layers will swell out from the hilum like gelatino us bags, the light blue communicated by the iodine serving to render them visible. It would seem that the outer covering slightly differs in its properties from that contained in the interior of the grain; being coloured violet by iodine, as seen both in the whole grain, when the outer surface shows the violet; and when starch is heated for a short time in a large quantity of boiling water, and allowed to settle, the white sediment gradually deposited, separated from the liquid and examined by the microscope, shows the appearance of a gelatinous membrane, and, when tested with iodine, shows the same or similar violet colour to that which appears on the outer surface of the whole starch grain. The latter may be soaked for almost any length of time in cold water without apparent alteration; but if potato or arrowroot starch are pounded in a mortar, some of the grains will be seen crushed in various ways, the broken edges being covered with sharp angles. If rubbed up with a little cold water, and the liquid filtered, we obtain a white opalescent liquid, which deposits no sediment, and no filtering will clear, evidently an imperfect solution of starch; treated with a proper quantity of tincture of iodine, it shows the same royal blue as perfectly dissolved starch. This is obtained by boiling a small quantity of starch in a large quantity of water, when a perfectly clear liquid may be obtained by filtering, containing a small quantity of the starch in a perfectly dissolved state, which is shown by the royal blue above mentioned, being produced by the action of iodine. Rice starchi treated in the same way gives similar results, only the smallness of the grains render it inconvenient for experiment. The iodide of starch produced is insoluble, or very slightly soluble in water; for if a small piece of solid iodine is dropped into the solution, the blue compound forms around the piece of iodine, while the liquid alone remains in appearance clear, though if the iodine be added in form of tincture, the blue compound never settles from the liquid in which it is diffused. Dry starch grains treated with iodine vapour (placed in a closed bottle with iodine) gives rather different results. The mixture commonly sold as arrowroot (arrowroot adulterated with potato) is coloured yellow sand; starch from the underground stem of Calystegia sepium (wild convolvulus) light brown, with all the rest, I tried-namely, Indian corn, wheat, horse radish, rice, and fennel. I obtained a violet after about a day's exposure to the action of the vapour; all showed a violet colour on being dropped into water. Starch is precipitated from its solution by solution of galls, and partially by acetic acid, some being precipitated and some remaining dissolved. The action of acids, &c., on starch is so well known that I may well leave out any further remarks on that subject. But in a future paper, if desirable, I may say a few words on the office performed by starch in nature, the nature of its production, and the means used to detect its presence. J. C.

SLOT CUTTING.

The

SIR-I beg to tender my thanks to our obliging "J. K. P." for his reply on the above subject. I had, of course, no wish to put him to the trouble of searching the back volumes, and was not unreasonable enough to expect him to do so. I have now looked through the "Notes and Queries" of the whole series, but, I regret to say, without success. question was, therefore, probably embodied in some longer communication. What the writer required was the means of cutting, in the lathe, the slots in the back part of pianoforte keys through which brass pins pass that hold them in their place. I looked out for an answer to this question, because it struck me that the solution would indicate a ready, expeditious, and accurate mode of cutting mortises in small articles of joinery. I almost fear the tool suggested by J. K. P." is more adapted for metal than wood, as the cutting edge would be scarcely keen enough for the latter. Nevertheless, I shall try it. I

was unaware of the shortness of the period during which "J. K P." had been a contributor to the ENGLISH MECHANIC. and am really amazed at the large amount of valuable information he has afforded in that time. F.R.C.S.

THE WORKMEN'S INTERNATIONAL

EXHIBITION.

SIR, In answer to those of your readers who have not received any answer to their letters to me, I beg to say that although I am perfectly willing to afford them all the information and assistance in my power, I cannot afford them stationery and postage stamps as well, my services to the Workmer's International Exhibition being honorary. They will therefore please to understand that the the post is, that they omitted to send stamped directed reason why they have not received answers through envelope for reply. ROBERT BURGESS, 22, George-street, Oxford-st., W., Local Sec., W.I.E.

[ocr errors]

taire-Wardour-street Lathe" is an offspring of Mr. Smith's "Jersey Lathe," and I hope at some future time to send you a few blocks of rosette work, with photographs of other things done in the lathe that will set the wits of the fancy turning fraternity to work-a lesson not easily accomplished.

Your correspondent "J. K. P." does not seem satisfied with the description of the Saltaire-Wardourstreet lathe, inasmuch as it does not mention Mr. Evans as the maker. He also states that Mr. E. did not make the overhead motion, only did a few alterations. If these alterations consisted in discarding certain parts and substituting his own improvements, it is very questionable whether it would not have been better let alone, and when J. K. P." states that he knows a great part of the lathe made at Saltaire was put on one than he can prove. side and entirely re-made, he states, I think, more believe a double crank shaft made at Saltaire was disto name the parts that were laid on one side? I Will "J. K. P." be kind enough

carded and substituted with one of Mr. Evans's improved single crank shaft-a very doubtful improvement indeed; I also believe that the standard, bed, heads, wheel, and other parts, such as leading screwsaddle, overhead motion, &c., was all or nearly finished before Mr. Evans had it, with the exception of polishing, and that the same had not been discarded." not aware that there are any of Mr. Evans's improvements in the lathe except the slide rest and single crank shaft, both of which were directly opposed to the designer's notion of lathe making. A NATURAL FLAT.

ASTRONOMICAL.

I am

FISHING RODS AND FISHING. SIR, I have, as an amateur, made a good many salmon and trout fly rods, and have tried all woods except the one mentioned by "The Harmonious Black smith." What I always aimed at, was lightness and strength; if I had this, I was pretty certain to have both elasticity and firmness. After trying all woods, I succeeded in making a salmonand a trout rod which pleases every one who handles them the first was 18' 6" long. Memel butt, hickory middle joint, lancewood and bamboo top, weighed 21b. 3oz., and pulled out last season many a fine 15 and 201b. salmon. The SIR, I am sorry that "Veritas" took exception to trout rod is 11' 6" long, ash butt, hickory middle, and my using "qualified" in my note; I did so because I lancewood and bamboo top, weighing 14oz. without do not profess to be so myself, not being a mathemathe reel, and seems in the hand like a willow wand. the books, and as "Veritas" had used quantities (as tician, but only working from the formula given in I should like to see some matters relating to shooting and fishing, now and then in your journal; these are coversine of are) not mentioned by any authors, I always interesting to both rich and poor, and when I wished to know if he was right in doing so, or whether am thus in the field, or more properly, the water, he was misleading any of your readers taking interest would like very much, if some of your sporting readers zontal parallax from the distance, and not the distance in the subject; and he also deduced the mean horicould give me a wrinkle how to catch mullet. I have tried them with every bait I can think of, from slob from the mean horizontal parallax, which is, I believe, worms to boiled cabbage, and find myself circum-diameter of the earth for determining that distance. the only data in conjunction with the equatorial semivented. They are to be seen in large numbers during the summer and autumn months, lying motionless in the timber ponds, many of them 10 and 12lb weight, allowing one to go within a few feet of them, if quietness prevails, but the moment a line is thrown, away they go. VIVIS SPERANDUM.

A CORRECTION.

SIR, I am afraid I must plead guilty to having committed a slight inaccuracy in the expression of the formula referred to by G. Firth, if it appears in the last volume, as stated by that gentleman in your last impression. Anyone versed in astronomical formulæ and expressions would see the error at once, and be able to rectify it, but to those who have not experience in those matters, I doubt not it is sufficiently puzzling. Of course by is not intended the log. dist. but the dist. The formula will then offer no difficulty. = 0.7215 0-4210 0-9919

[ocr errors]

=

=

[merged small][merged small][merged small][merged small][merged small][merged small][merged small][merged small][merged small][merged small][merged small][merged small][ocr errors][merged small][merged small][merged small][merged small][merged small][merged small][ocr errors][merged small]

THE SALTAIRE LATHE. SIR,-Your illustration of Mr. Salt's lathe must have delighted many of your readers; but the poor description pinned to its tail must have equally disappointed them. Your amateur turning friends will be much puzzled to know how many of the self-acting motions are obtained, to say nothing of a host of other intricacies in such an elaborate and costly piece of work. Very complete it may be said, no doubt, but not the most complete lathe in existeuce by many a bit. A lathe designed and made by Mr. Smith for his own private use is a far more complete machine, and it may be said without fear of contradiction that the Sal

Thanks to "R. H." for his information from the "Phil. Trans." He is not perhaps aware that all too small, and that the equatorial horizontal parallax astronomers have agreed that that determination was 8"-91 is now considered to be about from observations 895 of Mars at opposition, and also from the velocity of light, and that this value is also supported from a rediscussion of the original observations of the transit of Venus by Cooke, recently communicated by Mr. Stone to R. A. S.

I submit that the equatorial semi-diameter of the earth is the proper quantity to use, the mean semidiameter being the radius of the earth in latitude 45°+ and is only of value in determining the local parallax of any object from the geocentric position.

If Mr. Beardsley is the possessor of a telescope, will he allow me to suggest an analogical test as to the earth's rotation and sphericity? If he will observe the sun for some days in succession he will see spots traverse the surface from east to west; Jupiter or Mars, for some hours, markings traverse the discs in the same direction. Now if he will allow that these spots and markings are actual features of those bodies, he must also allow that there is motion on an axis, and as the object always maintains a round disc, this proves that they are spheres, as if merely circular discs, as they revolved they would alternately show as circles, then as ellipses, and finally as thin lines of light, according to their thickness. If the sun and the other planets are spheres, why the earth different? Also to consider that a sphere gives the largest surface with a given diameter, further, that it is the most convenient form for oceanic or terrestrial communication in any direction. I think he must allow this as strong collateral evidence.

Allow me to suggest that your space is too valuable to be taken up by mere verbiage whether "harmonious" or otherwise, and that useful information would be more acceptable to the bulk of your readers than personalities of any kind. S. B.

THE SUNFLOWER, &c.

SIR,-I have read the communication of "Tautau" on the many useful qualities of the sunflower with much interest, and have pleasure in transcribing the substance of a late address on "Plants as Sanitary Agents," by Mr. Ingram, at Leicester. The lecturer explained how plants and trees absorbed the moisture from the earth, which would otherwise appear in miasmatic vapours. Vegetable action produced oxygen and freed the air from taint, so that the multiplication of trees, shrubs, and plants increased the vital principle of the air and helped to get rid of its impurities. All trees are of course not alike in taste and constitution. Those which are deciduous, with large woolly or hairy leaves are not suited for towns; the particles of carbon which float in the air, re-ting on the leaves, often destroy them. Pines and firs require a pure air. The lime, plane, sycamore, elm, and chestnut, are amongst the trees that will thrive in towns. Low. marshy lands are greatly improved by heavy cropping. London sewage has made the poor sandy wastes of Barking Creek wonderfully fruitful. Vegetation seeks support, and seizes upon the pabulum within its reach; nothing, for instance, is too gross for a hungry and healthy vine. A singular fact was adduced in proof of the power possessed by plants to neutralise noxious exhalations. The observatory of Washington is situated in a dead marsh, the result of which was, that the assistant astronomers were killed off wholesale. Sunflowers were sown all round, and they reached their greatest luxuriance at the time when the fever was most rife; and the happy result was, that the fever disappeared, whilst the plants flourished on the poison that had committed such havoc. It was further suggested by Mr. Ingram that

« ZurückWeiter »