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scent line a platinum wire was used, which, when heated in a flame, was brought to a temperature near to its melting point by passing an electric current through it. The phenomenon in question is easily explained upon the supposition that the sodium flame absorbs rays of the same degree of refrangibility as those it emits, whilst it is perfectly transparent for all other rays."

We may just notice here that throughout the quotation we have made, the lines D are spoken of, whereas in our diagram (Figs. 5 and 6) we show a single line only. The fact is, that it requires several prisms and considerable magnifying power to show this line double, and inasmuch as it is extremely unlikely that any of those for whom we are writing will be in possession of the exceedingly powerful and very costly instruments needful to show D as two lines, we have spoken, and shall continue to speak of it merely as one.

To return, however, to Kirchhoff's capital experiment. He had, in effect, produced artificial sunlight, for upon the continuous spectrum given by his incandescent lime, or platinum wire, he had obtained the dark line of sodium. Now what does this mean?

[graphic]

(To be continued.)

A PRACTICAL TREATISE ON THE
HARMONIUM.*

BY HERMANN SMITH.

THIRD DIVISION.-CHAPTER III.
OF THE UPPER SOUND-BOARD, OR SWELL.

(Continued.)

"IT produces such an agreeable sensation to employ one's self about something of which one has only a half knowledge, that no one should reprove the amateur for meddling with an art which he can never thoroughly learn, neither should we blame the artist if, passing the limits of his peculiar art he chooses to recreate himself in an adjoining field."GOETHE.

THE

bear more than their share of deterioration. [ of wind. The wind does not now enter by the
Whilst we deplore such results, it is but fair we
should remember that trade and art are distinct
in aspect. Competition in trade, emulation in
art. It is a piece of the world's good fortune
when the two are found harmoniously united.
In justice to the amateur we will suppose him

FIG. 2

HE plan illustrated in the former chapter was suitable for an iustrument in which length could he allowed, whilst restricting depth from front to back as much as possible. The plan now presented is designed for harmoniums which we suppose permit us freely to consider the most advantageous arrangements in the general construction favourable to musical effect, and to this end several new features are introduced which on a little reflection you will perceive aid the resonant powers of the instrument, and give breadth and volume to the tone: in the front the space over the pallets is entirely enclosed, and at the back, covering the whole area of the soundboard, a large body of air is held vibrating in sympathy. The circulation of a large amount of air in the harmonium has an important value which no amateur should overlook. As springs to a carriage secure an easy sway to its motion, so this air cushion sustains and distributes with elastic swell the thousand shocks of vibration initiated by the reeds each time that they freshly start into eager speech. Hence it is that in large harmoniums we can always play more softly with continuous sound than upon small sized instruments. The leading principle in construction should be plenty of air and plenty of wood. The tendency of manufacturers is to the contrary. Competition says, Restrict both, give as little wind as you can scheme along with, for it costs money to enclose it, sell as little wood as you can for your bargained price, reduce proportions everywhere, and whenever possible, make three harmoniums out of the wood that your rivals, less gifted in contrivance, are consuming for two. These traders are not altogether to blame; it is a necessity forced upon them by the nature of the competition, which demands lowness of price, until it to be anxious for the best, and generous in the bespeaks indifference to quality or value. The time and material he devotes to his labour. In real fault is with the purchasers, in inability to discriminate real worth, or in deficiency of musieal taste, a state of things which tells sadly against the cause of true music, and is particularly hard against harmoniums, which have to

The copyright of this treatise is reserved by the Author. It was commenced in 94, and continued in No. 96, 98, 100, 105, 109, 116, 118, 124, 126, 132, 133, 136, 141, 151, 153, 166, 172, 180, 190, all of which are to be had except No. 98.

this work of the valve-board the wood should be
very clean, of picked quality, free from knots;
an inch thickness will not be too much, the frame
round it also as thick, and firmly fitted to the
back-board. The central portion of the back-
board is removable, for the purpose of adjusting
the valves or springs, as occasion may require.
When in p sition it is screwed to the frame of
the valve-board, which has previously been faced
with thick soft leather, to prevent any escape

ends of the sound-board, but through a valveboard, in the same manner as it does in the horizontal disposition of the sound-board, and the trunks rise from the back of well, the upper valveboard being a fixture upon them. In order to open the valves we have stop rods, and flaps, and levers working in the usual manner, and then obtain a reverse action by means of stems arranged on the bottom of well. A stem.as shown in illustration Fig. 2, is, by an ordinary sticker or poker, depressed at the nearend, and as the other end rises the rod connected with the valve rises and opens it. The place where this stem or lever should be pivoted you will calculate according to the amount of opening desired for the valve. Probably it I will be sufficient to open a valve only an eighth of an inch, or less, to lightly-voiced reeds. Or the amount of throw may be determined in another way. At right angles with each valve a small projecting arm is placed, which is hollowed or grooved underneath. Into this hollow the rounded end of the rods fits easily, and is held by a tapped wire screwed through the top of the arm into it. By this method adequate play is left for the movement of the rod, whilst the amount of throw exercised on the valve may be regulated by the position or distance at which it is pinned by the wire. The rod is still further steadied by little cross bars across the top and bottom of the trunks, drilled with holes, through which the rods are passed and allowed to work freely. These bars are very slight-mere guides-as it is not desirable by any obstruction to impede the free current of wind up the trunks. It may in some instances be of advantage to place springs on the stems that are fitted at the bottom of the well, but otherwise the springs upon the upper valves will return the rods, and retain them in contact with the stems.

The ends of the trunks are to be bound round with leather, and every care taken to prevent the least escape of wind. It is not merely the loss of wind that we are on guard against; the loss in itself may be very trivial, but it is the weakness thereby spread over the whole body of air enclosed in the well, a weakness materially affecting the articulation of the reeds, and the quality of tone likewise in the most subtle manner.

Over the pallets we are now able to obtain a more perfect mode of enclosure by extending the toning-board beyond the "touch" ends of the pallet stems. A rail is fixed along the lower edge of the sound-board, covered by a ledge projecting over the ends of stems, and perforated with small holes above each stem for the passage of tapped wires, which have buttons of leather or wood at each end, or perhaps only at one end, the other being screwed into the stem itself. When that mode is adopted the ledge should be slight, that it may not bind the movement of the wire, but when the wire is free, having its buttons

[graphic]

at both ends, then the ledge may be half an inch or more in thickness, and each hole be bushed with cloth; it is a little more trouble, yet is much the better method of the two. It is desirable you should be very careful to adjust all these buttons to fully meet the buttons tapped into the squares, for the reason that unless everything is in contact from finger to pallet, the touch and speech cannot be equal throughout in rapid playing, which demands that the speech of the reeds should be as prompt to the lightest as to the fullest depth of touch. All the particulars and instructions necessary for the amateur on the making and adjusting of stems, and pallets, and springs, and valves, having been fully detailed in former divisions of the treatise, it is not needful to repeat

them here.

In the last chapter the plan described admits of oue variation which the present one does not. In that, the sound-board may be fixed in its position whilst the hack may be made to be opened for the purpose of tuning. In some respects this mode is advantageous, as avoiding the risk of interfering with the adjustments of the front ac tions in the repeated turnings backward and forward during the process of tuning; the objections are that even to remedy a defect in a single reed, the instrument would require to be moved from its place, and that many tuners would find it inconvenient to tune to another person's fingering, or to go from front to back, time after time, through the whole of the tedious operation. Besides these there is another consideration, that when the lower manual is to be tuned it is an advantage to have the upper sound-board out of the way; on the other hand, if it is to remain a fixture, then space for opening the lower soundboard must be calculated and allowed for in lay

ing out the original design.

throughout, yet sound will penetrate through all.
Remember this, and you will understand why we
so insist on plenty of wood in the harmoniam to
mellow and ripen the quality of its tone. The
common practice has been to provide box and
shutter work in the most expensive class of in-
struments, and the makers have relied on such
means for softening the character of the harmo-
nium. The result has been the grave mistake of
producing a "forte" that is unbearably harsh
and disagreeable. It is an error you should sedu-
lously avoid in your own work. The harmonium
with open shutters should be considered the
normal condition, and you will ensure for that a
pleasant quality even at the fullest strength of its
sounds, just as in the organ the swell with free
open shutters is in its rightful relation to the fuil
organ. All modifications soften down from the
original standard, and every gradation of strength,
then, has its own charm. Unless you can attain
such light and shade, your harmonium may be a
pride to you as a memento of labour, but it will
hardly be what you would equally desire, a never-
tailing pleasure to listening ears. Opportunity
favours the amateur; he is free from the restric-
tion of competition, and study of the nature of the
elements he has to deal with may greatly stand
to him in the stead of experience.

ON

I

(To be continued.)

ORIGINAL EXPERIMENTAL RE-
SEARCH IN RELATION TO EMPLOY-
MENT FOR WORKMEN.*

T is an important national question, "By
what means can employment for workmen
in this country be increased?" My reply is,
"By encouragement of experimental scientific
research."

assist him. In some cases, however, the dis-
covery of a new truth in science, its application
by invention, and its practical carrying out, are
all effected by the same individual.

of

The

paper for the use of our daily press. numerous experimental investigations in relation to coal-gas have largely been the means of extending the use of that substance, and of increasing the employment of workmen and others connected with its manufacture. The discovery of the alkali metals by Davy, of cyanide of potassium, of nickel, phosphorus, the common acids, and a multitude of other substances, has led to the employment of a whole army of workmen in the conversion of those substances into articles of utility.

The foregoing examples might be greatly enlarged upon, and a great many others might be selected from the sciences of physics and chemistry, but those mentioned will suffice. There is not a force of nature, nor scarcely a material substance that we employ, which has not been the subject of several, and in some cases of numerous original experimental researches, many of which have resulted, in a greater or less degree, in increasing the employment for workmen and others.

The variety and extent of the employments which have resulted from scientific research are so great that they ramify in some form or other through nearly all our manufacturing, artistic and commercial occupations, our social relations, and our every-day life; and those employments have become of such common occurrence that we are apt scarcely to think how much experimental research has had to do with their production and we are thus led to undervalue original experimental investigation as a means of producing employment. Persons in general can easily will, in the course of time, become an oak, understand that an acorn planted in the ground wich, in the copalpable and visible effect; but they cannot so readily perceive that the abstract scientific fact discovered by experiment to-day, tical daily use, not because it is less real, but will probably soon become an invention of prac the senses, and requires a greater exercise of insimply because it is a phenomenon less evident to tellect to perceive it.

experimental science in new inventions has super-
In many instances, the application of original
seded, and, in a limited
manual labour, but it has in such cases either
sense, diminished,
substituted more intellectual occupation for it, or
has opened up new sources of employment to a
far greater extent by increasing trade and manu
facture. For example, the number of waggoners
and horses now employed to collect and deliver
all the goods for railways is much greater than
the whole of those employed for conveying the
goods of the country before railways were con-

structed.

In Fig. 3 we illustrate the preferable shape for side-irons to be used to the upper sound- I have observed that increased employment of board. You would require to have them made workmen constantly results from original expurposely, as all the side-irons in general use are perimental research in science in the following of the straight pattern. There will be no diffi- order: Experimental researches in science lead culty in getting these made at any village forge. to scientific discoveries; scientific discoveries The advantages of the shape are that the sound-lead to practical inventions; and practical invenboard, when it is turned forward to you, clears all tions lead to increase of employment. Usually, a the adjacent action with perfect freedom, and scientific investigator first discovers some new may be brought to a lower level, adding much to fact or principle in science; next, an inventor the facility and convenience in manipulating the applies this discovery, in the form of an invenreeds, and also a better set of the sound-board tion, to some useful purpose; and then a manuupon the valve-board is obtained, a closer pres-facturer or man of business brings it into sure on the wad, and consequently a more air- general use, and employs workmen or servants to tight fit. But to secure this latter advantage it is essential to regard the accuracy of the form and the fitting of these side-irons by taking care that the pivots on which they work are placed a little distance lower than the horizontal line The following examples will illustrate the of the lower edge of sound-board; if they were foregoing observation:-The discoveries The capability of developing increased emabove that line it is obvious that extra pressure at voltaic electricity, electro-magnetism, and mag-practically unlimited, because scientific discovery ployment by the means proposed is immense, and the upper hooks would only tend to part the lower neto-electricity, by Volta, Oersted, and Faraday, is quite in its infancy, and we are at present only edge of the sound-board from the wad, because led to the invention of electric telegraphy by on the very threshold of a knowledge of the forces if you strike a circle from the pivot, causing it to Wheatstone and others, and to the great manu- of nature and of the constitution of material subtouch the wad, and draw a horizontal line to the factures of telegraph cables and telegraph wire, stances; in this sense, therefore, experimental centre of that circle, the line being above the line and of the materials required for them. The scientific research may be viewed as the great of lower edge of sound-board, you will see that value of the cargo of the Great Eastern alone in fountain-head of employment for workmen. the descent of the circle is a retreat from the ver- the present Bombay telegraph expedition is caltical line of the valve-board, and the sound-board, culated at three millions of pounds sterling. It is the great fountain-head of industry in manuThe reason why original experimental science the more it is tightened by the upper hooks, will also led to the employment of thousands of factures and trades is, that it is only by incline away from the lower rim of wad, instead operators to transmit the telegraphic messages, of working up to it. However nicely you may and to a great increase of our commerce in means of such research that we can become acadjust the sound-board at the onset, yet you will nearly all its branches by the more rapid means stances involved in manufactures, and be enabled curately acquainted with the forces and subfind that the repeated opening and closing during of communication. The discovery of voltaic tuning will so flatten the wad that the hooks electricity further led to the invention of electroto use them to the greatest advantage. The will work loosely, and you must tighten up the plating, and to the employment of a large is shown by the fact that when new scientific intimate connection between science and industry eyes, screwing them in a turn or two more. The number of persons in that business. The numelower edge cannot thus be tightened up, and rous experimental researches on specific heat, ventors who immediately endeavour to apply discoveries are published there are numerous intherefore, with forethought, you will provide latent heat, the tension of vapours, the proper- them to useful purposes, and men of business against this by setting the sound-board originally ties of water, the mechanical effect of heat, &c., so that it will have to bear a greater strain during resulted in the development of steam-engines and ready to carry out the inventions practically. closing, and then by the time everything is com- railways, and the almost endless employment deplete and in working order, it settles down, pro-pending upon their construction and use. About a perly equalised in bearing upon the wad. quarter of a million of persons are employed on rail We have shown two pairs of forte shutters; ways alone in Great Britain, The various original these you can work in any convenient way, link investigations on the chemical effects of light led to them together, or arrange in Venetian swell the invention of photography, and have given emleather. A really effective "forte" can only be that process, or manufacture, and prepare the fashion, always careful that the edges bed upon ployment to thousands of persons who practise obtained in using shutters when means are taken various materials and articles required in it. The At the present time there is in this country no to secure a perfect box-like enclosure of the pal-discovery of chlorine by Scheele led to the inven- recognised payment for the labours of scientific lets-a crevice that will admit the passage of a tion of the modern processes of bleaching, and to discovery, and no provision for the support of sheet of writing paper will neutralise the best part various improvements in the dyeing of textile men who investigate science; any person is at of the shutters' effect; jus as the music from a fabrics, and has given employment to a very arge liberty to take the published results of scientific whole band will pass through a keyhole, so will number of our Lancashire operatives. The dis-men from the transactions of the Royal Society, the sound spread itself through the crevice. In covery of chlorine has also contributed to the the swell of the organ the sound cannot wholly employment of thousands of printers, by enabling e shut in; close it perfectly as ingenuity can Esparto grass to be bleached and formed int ontrive, line it with thickness after thickness of build it of 3in. thickness of wood

'rown paper,

* From Nature.

The great and important results already obtained by the cultivation of original experimental research show that it is a national necessity, and naturally suggests the idea, can we not by a greater degree of encouragement of such research still further increase employment for working condition? men, and still further elevate their intellectual

the Chemical Society, and other learned bodies, and employ them as the basis of inventions and patents, without the slightest payment, notwithstanding these results have been obtained at an immense cost of study, time, and labour, and a

large amount of money. I do not mean by these remarks to conclude that scientific discoveries should not, on publication, become at once public property, but that some means of support should be provided for the men who make them, and thus the development of employment for workmen be increased.

Experimental scientific research, in the stricter sense of the words, is a comparatively modern thing, and though it has existed in a more limited degree during many centuries, it can only freely exist and thrive in civilised countries. Even at the present time, in consequence of the peculiar nature of the occupation, its hopelessness as a source of emolument to the investigator, the great skill and extreme self-denial required, and frequently danger incurred in its pursuit, and the consequent great difficulty of achieving success in it, scarcely one person in one million of the population of England is exclusively devoted to it, although a much greater proportion occupy a small amount of their time in its advancement. The extension of physical and chemical knowledge by means of experiments and observations is national work: it benefits the nation, but does not pay the investigator. The various seientific men who discovered the chief facts and principles of science upon which steam-engines, electric telegraphs, and all the modern applications of science are based, received no remuneration for their researches. The results of purely scientific investigations are generally unsaleable, because, instead of benefiting a single manufacturer only, they benefit the whole nation; the nation, therefore, being the gainer, should pay and provide for those who make such researches. And when we consider that in this country upwards of 576 millions of pounds have been expended in the construction of railways alone, and immense sums upon electric telegraphs, which would never have been expended but for such labours, and nearly all of which have given employment to numberless workmen, it is evident that the magnitude national character of the results would fully just fy national encouragement of original experimental research.

an

The more abstract an experimental investigation is, the more important and widely diffused are its practical results. Who would have thought, when Oersted in his original abstract research in electro-magnetism first made a magnetised needle move by the influence of an electric current, that his labours would lead to the expenditure of many millions of pounds in the laying of telegraphs all over the earth, and the employment of many thousands of persons in their construction, maintenance, and use? And who can tell how many similar important discoveries have been lost to the nation, and how much of the present deficiency of employment for workmen has arisen in consequence of experimental scientific investigators not having been paid for their labours?

At present, original experimental researches are generally made by teachers of science who expend a portion of their incomes in making experiments and observations; but the very limited means of such men is a serious loss to the nation by greatly retarding the progress of discovery, and consequently also of improvements in manufactures. Many of the experiments, also, necessury for the development of new discoveries are beyond the means of such persons at present, and cannot be made without the command of greater

gestion has been made to the British Association than these substances, and is consequently more by Lieut.-Colonel Strange, to found "National active. All that has been said about the susColleges of Original Research," in which science taining and other properties of caffeine, in our should be investigated, but not taught. This coffee article, may be considered as applying also would be one way of supplying the want; the to theobromine. Cocan likewise contains a volafunds for supporting such colleges might with tile oil, similar to that of coffee: but it differs propriety be obtained from the fees paid for from the latter substance in possessing in a high patents, because patents are in many cases based degree fat and gluten, both of which tend to inupon the published results of original experimen- crease its nourishing properties. The fat, comtal researches; other ways of supplying the want monly called cocoa butter, may be extracted from might also be indicated. GEORGE GORE. the seeds by reducing them to a pulp, and squeezing them between two heated metallic plates, when the fat melts and is pressed out. It is of the consistence of suet, white and semi-transparent, and melts at 30 centigrade. It is principally stearin with a little olein, and has a peculiarly agreeable taste and odour,

POPULAR FOOD

TH

COCOA.*

ANALYSIS.

HERE is probably no article of diet with regard to the origin of which there is so From all this it is evident that cocoa is an exmuch confusion in the popular mind as that form-ceedingly nourishing, but, at the same time, a ing the subject of our present article. Cocoa nuts very rich article of food. Dr. Johnston, with and cocoa nibs, cocoa nut milk and cocoa oil, are good reason, compares it to milk, as follows:Cocoa. Milk (dried)

all believed to be derived from one common source.
This confusion arises principally from the circum-
stance, that the name of the substance which we
use as a beverage should really be spelt cacao,
and is as totally distinct a term, when so written,
from cocoa, as the two plants thus confused are
from each other. The cocoa nuts, so greedily
devoured in our childhood, au naturel or in the
form of cocoa nut rock, and which, in adoles-
cence, we knock off sticks on the Derby day, when
the champagne has developed our destructive
propensities, are the produce of the cocoa palm, or
Cocos nucifera; while, on the other hand, the
cocoa which we boil for breakfast is the seed of
the Cacao theobroma, a dwarfish, although pretty
tree, and very different from the gigantic palm
already mentioned. The Cacao theobrama is found
chiefly in South America and in the West Indies,
but is also cultivated to some extent in the Isle of
France, its principle commertial varieties being
those of Trinadad, Guayaquil and Bahia. It bears
a fruit not unlike a melon, in the soft rose-coloured
substance of which the cocoa seeds are embedded.
The seeds themselves are about the size of a large
almond, but somewhat thicker, and not so regular
in shape. Those from the two first-mentioned
districts are covered with a brown and bitter husk,
enclosing a somewhat pasty and deep-coloured
mass, which constitutes the useful portion; while
the seeds from Bahia, on the other hand, are
smaller, lighter in colour, and have in the interior
a tinge of greenish brown. The number of seeds
in the cacao fruit varies according to the districts
in which the tree is cultivated. When ripe, the
fruit changes from green to yellow, and it is then
gathered and opened; and the seeds having been
taken out, are dried in the sun, or are subjected
to a slight fermentation, by burying them in the
earth, before being dried.

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51

Fat or butter
Casein or gluten... 21
Sugar or starch... 22
Ash

Theobromine

100

24

35

37

100

But cocoa being richer in fat than milk, and consequently, more indigestible, some sanitary authorities are prepared to approve of its dilu tion, by means of starch and other such substances. This is, however, sometimes pushed to an extreme extent, and Dr. Normandy says: "Unfortunately, however, many of the preparations of the cocoa nut sold under the names of chocolate, of cocon flakes, and of chocolate powder, consist of a most disguting mixture of bad or musty cocoa nats.. with their shells, coarse sugar of the very lowest quality, ground with potato starch, old sea biscuits, coarse branny flour, animal fat (generally tallow, or even greaves). I have known cocoa powder made of potato starch, moistened with a decoction of cocoa nut shells, and sweetened with treacle; and chocolate made of the same materials, with the additions of tallow and ochre. I have also met with chocolate in which brick-dust or red ochre had been introduced to the extent of 12 per cent. ; another sample contained 22 per cent. of peroxide of iron, the rest being starch, cocoa nuts with their shells, and tallow. Messrs. Jules Garnier and Harel assert that cinnabar and red lead have been in certain samples of chocolate, and that serious accidents have been caused by that diabolical adulteration. Genuine chocolate is of a dark brown colour; that which has been adulterated is generally redder, though this brighter hue is sometimes given to excellent chocolate, especially in Spain, by means of a little annato. This addition is unobjectionable provided the annato is pure, which, however, is not always the case." Out of sixtyeight samples examined by the Lancet commission.. thirty-nine were found to contain ferruginous earths. (To be continued.)

Cocoa is manufactured for domestic use in various ways:-1. The seeds are very gently roasted till the flavour is well brought out, and, after being winnowed from the husks, are broken into little pieces. In this form they are known as cocoa nibs. 2. The seeds, having been roasted, are ground between hot rollers into a paste, and, after due admixture with starch and sugar, the paste is either desiccated and reduced to powder,-in which case STOCKWELL'S it is cailed "soluble," homopathie," "digestive," or any other attractive name or it is dried in masses, forming flake and rock cocoas. 3. The roasted and winnowed seeds are ground to paste, sugar and seasonings added, and cast into moulds, in which form they are called chocolate. Dr. If England is to keep pace with the progress Johnston states that the separated husks are largely of foreign intellect and of foreign manufacture, imported into this country under the name of and keep her workmen fully employed, there"miserable," and used for adulterating common must not only be a general diffusion of scientific cocoas, to form a cheap and agreeable beverage knowledge throughout this country, but there for the poorer classes! The composition of cocoa must also be national encouragement of original is shown by the following analysis by Mitscherscientific investigation.

wealth.

lich:

Theobromine...
Cacao Red
Cacao Butter...
Gluten

Starch
Sugar
Cellulose
Ash ...
Moisture

...

1.20 3:50

49:00

15:00

16:00

6.60

5:60

3.50

Has it been wise in our Governments thus to overlook a great source of the nation's wealth, to disregard a most important means of national economy, to neglect the great fountain-head of in instry? Shall we allow foreigners to supplant us in manufactures, and shall our fellow-men continu to be driven to emigration by want of employment? or shall we develop for them new sources of labour by means of original experimental research? It needs only to bring the subject fairly and effectually before the attention It will be noticed that cocoa possesses, like tea of our present enlightened and progressive and coffee, an active nitrogenous principle called Government, to ensure its careful and early theobromine. This principle resembles theine or

consideration.

The neglect of original experimental science in this country by our Governments has long been noticed by scientific men and others, and a sug-|

5:60

100·00

caffeine, inasmuch as it is also white, crystalline,
and bitter; but it contains more nitrogen even

* By J. MUTER, Ph.D., in the Food Journal.

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The nose of the hammer is made flat on the bottom, and set at right angles with the shank A. The shank is made of steel, and divided into inches and eighths of an inch. construction gives the square and the rule. one side of the hammer head is a point B, and a similar point is made on the head of the milled C. By loosening this screw, the shank A may be drawn out or thrust in to adjust these points to different distances, so that circles of various sizes can be marked out with them, as with compasses.

set scrow

On the opposite side of the head is a pointed hook D, which, in connection with the blade E forms the can opener. The pointed hook is thrust through the tin plate, as near as may be to the centre of the top of the can, and the blade E being pressed down through the tin, a sweep of the handle cuts out a circular dise, through which the contents may be taken out.

The end of the shank A opposite the hammer head, is formed into a screw driver. Loosening

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the set screw C allows the shank to be taken
out of the handle, when the chisel and gimlet E
may be taken out.
When either the chisel or
gimlet are required to be used, they may be
placed in the handle and held by the set screw
C, as the shank A is held when the hammer is
used. G represents the claw, which has at the
opposite end a marking awl. This can also be
used by fixing it in the handle with the set
Screw. By turning the handle so the knife
will be on the same side as the point, or hammer;
it can be used as a washer cutter for pump
valves, waggons, etc.

Patent allowed, through the Sciet ific American Patent Agency, April, to G. W. Sockwell, inventor, Natchez, Miss., U.S.

[blocks in formation]

The illustration represents the operations of the wood boring beetle. The insect when about to deposit her eggs, selects a tree of suitable size, and commences her operations on the bark. At the bottom of the illustration will be observed a small inclined ho'e, and at the end of this a beetle is to be seen; this is the little architect who, by the joint exertions of herself and her progeny, has so wonderfully penetrated the tree in every direction. Another hole, running horizontally across, will likewise be seen at the right of the figure, and in the end of this another beetle may be seen similarly engaged. When the exertions of the insect have prepared a sufficiently large hole, she then commences to lay her eggs.

OPERATIONS OF THE WOOD-BORING BEETLE.

But before procceding to this subject, let us just
dwell for a moment upon the magnitude of the
work she has accomplished.

The hole bored into the heart of solid wood is
about fourteen or fifteen times longer than the
body of the beetle, and the animal must, by the
help of its jaws, tear away and remove a bulk of
timber more than twenty times its own bulk. We
shall gain some idea of the amount of labour
necessary for this, by considering what would be
the corresponding work that should be executed
the beetle for this kind of work. He would
by a man, were he to be equally adapted with
have in a few days to bore into a mass of solid
timber a cylindrical hole, about eighty or ninety
feet long, and about three feet in diameter.

The central part of the illustration shows another stage in the history of these tunnelling operations. We will suppose that a beetle has finished the hole of which the two already described are the commencement. All along each of these will be seen little white spots; these represent the eggs which she lays as she proceeds. The long line in the centre of the figure represents a part of the completed hole, along the sides of which the eggs are laid.

ment it becomes conscious of its existence, the
food which nature intended for it surrounding
it in boundless profusion. At once it commences
to eat the wood that is under it, and thus it
speedily excavates for itself a little hole, the
bottom of which gradually deepens as the insect.
proceeds. Its brothers and sisters, likewise
hatched about the same time, commence each to
eat their small hole, and thus from the main
tunnel a number of small holes gradually extend
through the trunk, all commencing, of course,
sect.
from the hole originally made by the parent in-

Now, as the little grubs progress onwards, they at the same time grow in size, and their appetite consequently increasing, the hole gets gradually larger, and this is, of course, also necessary to allow for their increased dimensions. Gradually they proceed farther and farther from the centre, and approach nearer and nearer to the outside of the tree; but just before they finally emerge, when they are just beneath the bark, a curious change comes over them. They have now grown to be as large as their parent, but still they are grubs; they have not donned the legs and wings which are necessary for the perfect beetle, but the tree which has housed and fed them in their infancy still affords them shelter till their final development. As they get near the bark they cease to eat, and fall into an inert condition; but all this time a wonderful change is taking place within their bodies-they cast off their skin and are transformed into perfect beetles. Speedily they emerge from the tree to find themselves in a new and wondrous world, and to use and enjoy those powers of flight which they have so recently and so curiously acquired. Truly this is a very astonishing history; we have seen one beetle boring into a tree, we see a hundred emerge from it; the solid substance of the trunk has afforded nourishment to the numerous offspring. There is no more interesting department of natural history than that which treats of the habitations of insects; and there is, perhaps, hardly any insect This being understood, we shall not be sur-more interesting in this respect than this woodprised to find that when the eggs of the beetle we boring beetle. are describing are hatched, the young that come from them are quite unlike their parents. They are small white grubs, rather uninteresting in appearance, but endowed with a most tremendous appetite and vast powers of digestion. The food which supports the little grub is the solid wood of the tree itself. It will be remembered that each egg was deposited on the side of the hole, and there it remains attached until it is Latched; thus the little creature finds, the mo

When the eggs of the beetle are hatched, the little animal that comes from them is at that stage of its existence utterly unlike its parents. It is at first a little grub without legs, and quite as unlike a beetle as an earth-worm is unlike a house-fly; this is called the larva condition of the beetle; and it is equally true of every other insect, that in the early stages of its existence it is utterly unlike in appearance, in food, and habits, to the parents from which it has sprung. Thus the dragon-fly, with which we are all so familiar, and which is such an ornament to our streams, was, when young, an unattractive and somewhat ferocious-looking grub, wholly resident in the water, over which, when mature, it skims, but which it never touches. The food, too, of the larva of the dragon-fly is quite different from that of the mature insect.

MECHANICAL MOVEMENTS.*

(Continued from page 148.)

Continuous rotary motion of the cam

76. Contin a reciprocating rectilinear motion

to the bar. The cam is of equal diameter in
every direction measured across its centre.

Editor of the American Artisan.
Extracted from a compilation by Mr. H. J. Brown,

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is used in working small air pumps for scientific
experiments.

AND MIND.*
LECTURE I.

77. Col. Colt's invention for obtaining the move-, is communicated by the pinion to the racks. This, ON THE RELATIONS BETWEEN BODY ment of the cylinder of a revolving fire-arm by the act of cocking the hammer. As the hammer is drawn back to cock it, the dog c attached to the tumbler, acts on the ratchet b on the back of the cylinder. The dog is held up to the ratchet by a spring c.

78. C. R. Otis's safety-stop for the platform of a hoisting apparatus. A are the stationary uprights, and B is the upper part of the platform working between them. The rope a by which the platform is hoisted, is attached by a pin b, and spring c, and the pin is connected by two elbow levers with two pawls d, which work in ratchets secured to the uprights A. The weight of the platform and the tension of the rope keep the pawls out of gear from the ratchets in hoisting or lowering the platform, but in case of the breakage of rope, the spring e presses down the pin b, and the attached ends of the levers, and so presses the pawls into the ratchets and stops the descent of the platform.

84. Represents a feeding apparatus for the bed
of a sawing machine. By the revolution of the
crank at the lower part of the figure, alternative
motion is communicated to the horizontal arm of
the bell-crank lever whose fulcrum is at a, near
the top left-hand corner of the figure. By this
means motion is communicated to the catch at-
tached to the vertical arm of the lever, and the
said catch communicates motion to the ratchet-
wheel, upon the shaft of which is a toothed pinion
working in the rack attached to the side of the
carriage. The feed is varied by a screw in the
bell-crank lever.

turning the wheel to the right, motion is commu-
85. Is the movable head of a turning lathe. By
nicated to the screw, producing rectilinear motion
of the spindle in the end of which the centre is
fixed.

86. Toe and lifter for working puppet valves
79. Crank and slotted cross-head, with Clay-in steam engines. The curved toe on the rock-
ton's sliding journal-box applied to the crank-shaft operates on the lifter attached to the lifting
wrist. The box consists of two taper lining rod to raise the valve.
pieces and two taper gibs adjustable by screws,
which serve at the same time to tighten the box
on the wrist and to set it out to the slot in the
cross-head as the box and wrist wear.

ENTLEMEN,-The relations of mind and body in health and in disease I have chosen as the subject of these lectures, not with the hope of doing full justice to so complex and difficult an inquiry, but because it has for some time been my special work, and there was no other subject on which I should have felt myself equally justified in addressing you. No one can be more deeply sensible than I am how little we do know accurately of the bodily conditions of our mental functions, and how much of that which we think we know is vague, uncertain, and fluctuating. But the time has come when the immediate business which lies before anyone who would advance our knowledge of mind unquestionably is a close and searching scrutiny of the bodily conditions of

its manifestations in health and disease. It is

most necessary now to make use of the results of the study of mind in health to light and guide our researches into its morbid phenomena, and in like manner to bring the instructive instances 87. Pickering's governor. The balls are at- presented by unsound mind to bear upon the intached to springs the upper end of each of which terpretation of its healthy functions. The phyis attached to a collar on the sliding sleeve. siology and the pathology of mind are two branches of one science; and he who studies the The springs yield in a proper degree to the cenone must, if he would work wisely and well, draw the balls towards the spindle and depress I shall embrace the occasion whenever it offers and as the centrifugal force diminishes, they the reconciliation between them, and in doing so 88 and 89. The former is what is termed a re- itself, to indicate the principles which should very limited motion upon a pin, which is fixed coil, and the latter a repose or dead beat escape-guide our efforts for what must always be the in a block of cast iron, which is made with two ment for clocks. The same letters of reference highest object of medical science and art,-the jaws, each having a flange projecting inward in contact with the inner suface of the rim of the indicate like parts in both. The anchor H L production and preservation of a sound mind in a sound body. Actually to accomplish much of wheel. By the upward motion of the outward K is caused by the oscillation of the pendulum, this purpose will not lie in my power, but I may out the bearing of them on one another and on bring together fragmentary observations, point received opinions, thus unfold their meaning, and mark broadly the lines which future research

80. A mode of working a windlass. By the alternating motion of the long hand-lever to the trifugal force of the balls, and raise the sleeve; study the other also. My aim will be to promote

right, motion is communicated to the short lever, the end of which is in immediate contact with the rim of the wheel. The short lever has a

end of the short lever, the rim of the wheel is jammed between the end of the lever and the flanges of the block, so as to cause friction sufficient to turn the wheel by the further upward

movement of the lever. The backward movement of the wheel is prevented by a common ratchet-wheel and pawls; as the short lever is pushed down it frees the wheel and slides freely over it.

81. The revolution of the disc causes the lever at the right to vibrate by the pin moving

in the groove in the face of the disc.

82. By the revolution of the disc in which is

the sleeve.

to vibrate upon the axis a. Between the two ex-
tremities, or pallets H K, is placed the escape
wheel A, the teeth of which come alternately
against the outer surface of the pallet K, and
inner surface of pallet H. In 289 these surfaces

are cut to a curve concentric to the axis a ; con-
sequently, during the time one of the teeth is
against the pallet, the wheel remains perfectly

at rest.

Hence the name repose or dead-beat. In 288 the surfaces are of a different form, not necessary to explain, as it can be understood that any form not concentric with the axis 4, must produce a slight recoil of the wheel during the

mnst take.

Within the memory of men now living insanity was such a special study, and its treatment such a special art, that it stood quite apart from general medicine in a mysterious and mischieyous isolation; owing little or nothing to the results of progress in other branches of medicine, and contributing nothing to their progress. The

reason of this it is not hard to discover. The

fixed a pin working in a slot in the upright bar escape of the tooth, and hence the term recoil es habit of viewing mind as an intangible entity,

which turns on a centre near the bottom, both ends of the bar are made to traverse. the toothed sector producing alternate rectilinear motion in the horizontal bar at the bottom, and also alternate perpendicular motion of the weight.

83. By a vibratory motion of the handle, motion

capement. On the pallets leaving teeth, at each
oscillation of the pendulum, the extremities of
teeth slide along the surfaces c, e, and d, b, and
give sufficient impulse to pendulum.

90. Another kind of pendulum escapement.
(To be continued.)

the notion of it as an incorporeal essence, which science inherited from theology, prevented men

*Two lectures delivered at the Royal College of Physicians in 1870. By HENRY MAUDSLEY, M.D., F.R.C.P., Professor of Medical Jurisprudene sin University College, London.

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