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part of the matter forming a nebula is invisible, we remove the immense difficulty which we otherwise experience in attempting to conceive how nebule have assumed or can retain their extraordinary shapes and yet be subject to the law of gravitation.

The researches of Huggins prove that many of the nebule are gaseous self-luminons masses, whilst the spectra of others prove the existence of solid or liquid matter. These last being generally those which are most easily resolved, would be those which have been longest in existence, and which, therefore, should contain most liquid and solid matter.

The curious shapes of the nebula are well explained on this theory.

Thus the spiral nebulae would be produced by two masses of gas rushing together and forming an eddy in which they become mingled with each other. If any detached portion of one gas got mixed up with the other gas, it would be drawn out by the eddy into an elongated spiral form, the earface of which would become visible by the light produced by the chemical action. This would be the kind of nebula which would be produced when the two masses of gas did not differ greatly in size, and rushed together in a line not very oblique to the line joining their centres of gravity.

be

Annular nebula might be formed in the follow-
ing manner. If a small mass of gas were at-
tracted to a larger mass so as
just to graze its surface on pas-
sing it, its path (previously pa-
rabolic) would become elliptic,
and its motion would
changed into a periodical re-
volution round the larger mass.
At each revolution it would Lassell, pl. 1. fig. 4.
graze the surface of the larger
mass, and the elliptic orbit would gradually be
changed into a circular one.
would at length come to re-
volve about the larger mass in
such a manner as continually to
graze the surface, and an annu-
lar nebula would be the result.

It

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Those nebulæ, like the larger
one in Andromeda, in which
streaks of darkness cross the
bright parts, offer the greatest Nebula in Lyra.
difficulty in their explanation.

We might imagine that a mass of rare gas has
become entangled between two;
masses of dense gas, and that
the masses of dense gas being
attracted to one another, crush
out the rare gas into a thin sheet,
which, looked at edgewise,
presents the appearance of a dark
streak.

Some of the nebule of this
kind have nuclei; and it may
be remarked that the position of
the nucleus, which will be the
centre of gravity of the nabulæ, is
in the position in which we should
expect to see it if the appa-
rent vacuous streaks were in
reality filled with matter.

Lassell, pl. 5.
fig. 21 A

Many of the nebulæ are very much diffused, and in shape very irregular; but even these show certain characteristics which seem to indicate their mode of Some spiral nebulæ consist only of a single formation. The extreme faintwhirl. A nebula of this kindness of their light favours the hypothesis that they might be produced by a are not luminous throughout, but that their lumismall mass of comparatively dense gas rushing obliquely into a large mass of rarer gas. Such a mass would tend to the centre of gravity of the larger mass; and since those parts which

Lassell, pl., 1. fig. 3.t are nearest the centre of

gravity would be most accelerated, it would become drawn out into an elongated spiral form.

After a time the whole of the smaller mass of

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gas will have collected about the
centre, and a globular or planetary
nebula will be formed.

In the annexed diagram, copied
from a drawing by Lassell, we ap-
Lassell, pl. 7. pear to have a globular nebula in the
fig. 30. process of formation. That the
smaller mass of gas has entered
obliquely is shown by the fact that the
ending a b of the
tubular portion is
oblique to the axis
of the tube; for
the line a b will
indicate the boundary
of the larger mass.
That the gas is collec-
ting about the centre
of the larger mass is
indicated by the fact
that the line o c join-
ing the centre of the
globe with the end of
the tube is perpendi-
cular to a b-as it
should be, supposing
the larger mass of a
spherical form.

Lassell, pl. 2. fig. 9.

Planetary nebula, consisting of more than one envelope might also be formed in the same way as those having only one envelope, the envelopes being formed in succession at different periods

of time.

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Lassell, pl. 5. fig. 21.

nosity occurs only here and there in comparatively
thin shells.

the intensity of their light should be greatest
Again, if these nebula were luminous throughout,
where the thickness of matter looked through is
greatest. and should fade away at the boundaries,
the boundaries should appear brighter than other
whereas, if the visible parts occurred in shells,
parts; for at the boundaries the line of sight
would be very oblique to the shell, and a greater
thickness of luminous matter would be looked
through. Now if we examine any of the irregu-
lar nebula, we see some parts of it ending
abruptly with a clearly-defined outline, whilst in
other parts the light gradually fades away into
darkness. We may suppose that in the one case
we are looking edgewise at a shell, so that the
line of sight is tangential to its surface, whilst in
the other case we are looking at a part where the
luminous shell gradually thins out. Now in the
first case we find that the light increases towards
the border, consistently with the supposition that
the visible parts are in thin shells.

This peculiarity is, I apprehend, what Professor
Bond and Mr. Lassell refer to when they speak of
the scroll-like appearance of the nebula in Orion.
In those nebula which appear to have assumed
a more stable form, as in the elliptic and circular
nebula, the light diminishes from the centre to
the circumference.

mation; they may have become more condensed,
These nebulee may be in a later stage of for-
and a more intimate mixture of the gases may
have taken place, and in consequence they may be
and the fact that they are generally resolvable in
more or less luminous throughout. Their shape,
the telescope, point to the conclusion that they
have been a long time in existence.

Before turning to the subject of comets, I may remark that the theory that there are large masses of invisible gas traversing space, affords an explanation of the sudden temporary outbursts in the intensity of certain stars. Such an outburst might occur if a star became enveloped with a mass of gas with which it could cheniically combine.

It also explains the phenomena of periodical stars. Mr. Huggins has found that the diminution in the intensity of the light of these stars is due to an increase in the number and size of the

absorption bands in their spectra.

It has already been suggested that large opaque bodies may be revolving in orbits round such stars, and periodically obscuring their light. We have only to suppose that large masses of invisible gas instead of opaque bodies revolve about them, to explain the phenomenon in accordance with spectroscopic observation.

(To be concluded next week.)

FRICTION IN STEAM CYLINDERS.*
BY MR. P. JENSEN.

NO few data exist on the subject of friction in it with some diffidence, more especially as he has not had time to make direct and comprehensive trials which would furnish particulars for exhaustive treatment of the subject. He, therefore, can only offer such remarks and make such deductions from the experience of others and of himself that have a bearing on the subject, without assuming to settle questions relating thereto. Of the importance of the subject there can be no question, as engineers are aware of the great percentage of power that may be consumed in piston friction. Hence it is well to define this loss under various circumstances, and then to apply remedies for diminishing the loss. Friction in the steam cylinder may be classed under three heads; piston friction, slide valve friction, and stuffing box friction. As regards piston friction it ought to depend upon the working pressure, the packing material employed bing surface of the packing, and the means of for keeping the piston tight, the extent of the rublubrication. It is evident that a piston should not be made to stand a higher pressure than that it is intended to work with, otherwise a great amount of power may be lost by unnecessary friction, and wear and tear both of piston and cylinder will ensue. It also appears evident that engines expanding the steam to any great extent in one cylinder should have piston packing, the tension of which is dependent upon and constantly vary. ing with the pressure of the steam at any part of the stroke. There is not, it is believed, any difficulty in this, and all are doubtless familiar with which answer the purpose in a greater or less one or more constructions of pistons of this sort degree.

piston friction by assuming a certain constant presThe common rough and ready way of calculating sure per square inch of piston as being the measure for the piston friction (which, as will be seen the total friction) of the engine itself is erroneous, presently, constitutes by far the greater portion of or at any rate should be used with discrimination. Although it has been found in a few instances that the friction of a piston for instance in an engine working with 2 atmospheres may be expressed by (say) 2lb. per square inch of the piston, which may or may not mean that the piston packing has had just the requisite amount of tension, and not perhaps 50 per cent. more than requisite, we have no right to infer that the same rule holds good with 5 or 10 atmospheres pressure. If the piston packing has just the right tension, the friction must amount to a certain percentage of the pressuxe. But we must not lose sight of another circumstance-namely, that the circumference of a piston increases as the diameter simply, while the area increases as the square of the diameter.

double the amount of friction, or has it four times Ths question is, has a piston of 24in. diameter the amount of that of a 12in. piston, other circumstances being alike, that is, with the same material, same depth of packing, state of lubrication, pressure, &c. We must not forget either that the diameter of the cylinder. Whether it is supposed proportionate depth of packing varies with the to give less wear on the piston rings (an opinion considered incorrect by the author) or not, we not to increase the depth in direct proportion as need not stop to discuss; the practice is, however,

*Read before the Society of Engineers, March 7, 1869.

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A MICROSCOPE.

the diameter of the piston increases in size, and HINTS ON THE SELECTION AND USE OF ON THE RELATIONS BETWEEN BODY thus it is that the piston friction does not in practice decrease in the ratio otherwise anticipated, though it is believed that it does decrease. In other words, it is propounded that piston friction as

THE quality of a microscope, says the Techno-
logist, of course depends entirely upon the

AND MIND.*
LECTURE II.
(Continued from page 243.)

[T is a natural question, Whence come these

percentage of power decreases as diameter increases, perfection with which it shows objects as they animal traits and instincts in man? Whence

=

=

but increases as pressure and depth of packing increase, the packing material being the same. In practice the following rule holds good:-Depth of packing d in inches for instance, for a 19in. cylinder, depth of packing = × 7 = 5}; for smaller engines, Vd (say) 16in. cylinder, depth of packing × 4 23in. This is for cast-iron packing rings. With Ramsbottom's steel ringsa much smaller depth is found quite sufficient. Hence if it is found that 21b. per square inch is the measure of the piston friction in a 12in. cylinler, it would seem that the friction of a 24in. cylinder (having four times the area but only double the diameter), would only be double, but as the depth of packing is as 2-3 to 3-89 it would

3.89

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cylinder, and 21b. in a 16in. This is of course assuming the ordinary theory of piston friction to be correct, namely, that it is to be calculated by the superficial area of the piston packing X the pressure of the steam X the friction, co-efficient. If, then, the above be correct, it is clear that we must avoid taking a certain fixed percentage of the pressure on the piston area as the measure of the piston friction, except we take the size of the cylinder into account.

really are.

Some microscopes distort objects so was derived the instinct which taught the idiot as to give views that are anything but correct. Others colour whatever they show with all the Woman to gnaw through the umbilical cord? Was brilliant hues of the rainbow. We have often it really the reappearance of a primitive instinct admired the magnificent colours displayed by of animal nature-a faint echo from a far distant natural objects under the microscope, such, for past testifying to a kinship which man has almost example, as the petal of the geranium, whose cells outgrown, or has grown too proud to acknowledge? are filled with the most brilliant scarlet colouring No doubt such animal traits are marks of extreme matter; or the crystals of the ruby oxide of cop-human degeneracy, but it is no explanation to call per, which are gorgeous beyond expression; or them so; degenerations come by law, and are as various objects seen by polarised light, which natural as natural law can make them. Instead gives to some of the most colourless and trans- of passing them by as abnormal, or, worse still, parent crystals colours that far excel the tints of stigmatising them as unnatural, it behoves us to the ruby or the sapphire; but we have often seek for the scientific interpretation which they smiled when asked to view the splendid colour must certainly have. When we reflect that every shown by hair, or a fly's eye, or a section of wood human brain does, in the course of its developseen by ordinary transmitted light, for we well ment, pass through the same stages as the brains knew that these objects have no colour of their of other vertebrate animals, and that its transiown, or at least only dull, neutral tints, and that tional states resemble the permanent forms of all the gorgeous hues so lavishly displayed were their brains; and when we reflect further, that merely the result of defects in the microscope. the stages of its development in the womb may It is unquestionably true that one of the fine be considered the abstract and brief chronicle of large achromatic microscopes, furnished with ob- a series of developments that have gone on jectives of low as well as high power, would be through countless ages in nature, it does not seem the best for all purposes of examination. But so wonderful, as at the first blush it might do, such microscopes are very expensive. A tolerable that it should, when in a condition of arrested one cannot be had for less than one or two hun-development, sometimes display animal instincts. dred dollars, while a first-class one will cost four Summing up, as it were, in itself the leading or five times that amount. Such a microscope, forms of the vertebrate type, there is truly a brute although desirable, is not absolutely necessary, brain within the man's; and when the latter stops and therefore we will turn our attention to the short of its characteristic developement as human less costly kinds. -when it remains arrested at or below the level of an orang's brain, it may be presumed that it will manifest its most primitive functions, and no higher functions.

The first that presents itself is the simple lens The packing material has considerable influ- mounted in a metal or horn frame. In the hands nece on the friction. Hemp packing for moderate of a skilful observer, this instrument will do good and for high pressure causes more friction than service. Opticians frequently arrange several metallic packing, which is now almost universally lenses in one frame, and suggest the idea of comadopted. Cast-iron rings or Ramsbottom's steel bining them so as to obtain an increase of power. rings, though not giving so little friction as gun In general, however, this idea is fallacious, and metal, are generally preferred, because they wear well and are not so much affected by grit. The author's experience is that Ramsbottom's rings are tight, wear well, and do not require excessive tension. For great expansion in a single cylinder the tension of the packing should be dependent upon the varying pressure in the cylinder, as before stated.

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the instruments are not properly arranged for the
purpose. In the first place, there is no diaphragm
(or thin plate with a small hole in it) between the
lenses to cut off the extra light; and, in the
second place, the lenses are placed as close to each
other as possible, so as to occupy but little room,
and this prevents us from obtaining a good effect.
Moreover, it is unfortunately true that opticians
(somebody once called them in derision shop-
ticians) rarely give us the best selection of powers.
There is too much sameness in them. The best
arrangement we could find in a large ellection
consisted of three lenses, whose magnifying
powers were respectively 25, 20, and 16 diameters.
Now, this is not variety enough, and the reason
for not making a greater difference between the
powers of the lenses is the fact that high powers
are so much smaller than the lower powers that
to combine them in the same frame makes a
clumsy instrument. We confess, however, that
we would much prefer efficiency to elegance.

A frame containing three plano-convex lenses,
Iin., in., and fin. focus, we have found altoge-
ther the most convenient arrangement. The mag-
nifying powers are 10, 20, and 40 diameters; and
whether we desire to examine a mineral, a flower,
or an insect, whether we wish to look at the mil-
dew on a grape-leaf or the beetle which prevs upon
the buds, such a series of powers will enable us to
do so thoroughly.

In considering the question of stuffing box friction, the author would first observe that the amount of loss caused by it is only trifling if the packing is in proper condition and the gland has been properly fitted; but otherwise this loss may be come enormous. The author is not aware of any comparative experiments showing the friction caused by the employment of various kinds of stuffing-box packing, although that, doubtless, has also a great influence. But what all are aware of is the great wear on the piston rod through having the packing too hard. A careful engine driver avoid this, but every engine driver is not careful, and if he has many other things to look to, as is often the case, then the plain question arises whether it is not better either to use a packing that requires but little lubrication, or else to provide means for keeping the packing continuously supplied with a very slight amount of grease, which, as experience has shown, can be effected by greasing the steam before entering the cylinder. No other means are then found necessary for lubricating the slide rod or piston In selecting single lenses to be used as microrod, and hard packings become an impossibility. scopes, procure, if possible, those of which one It is not intended to describe the various kinds side is perfectly flat, that is to say, plano-convex. of packing; suffice it to say that there are some The view obtained by such lenses is always better which answer their purpose very well, some of than that given by donble convex lenses of the them requiring little or no lubrication. The self- same power. Such simple microscopes are unlubricating mineral packing has under some cir-doubtedly the best cheap instruments. But at cumstances answered very well. Metallic stuffing a very slightly higher cost we may obtain that box packing has been proposed and used. On best of all simple microscopes-Wollaston's account, however, of the great depths required doublet. This microscope is formed of two planoand the expense and trouble attending its manu- convex lenses adjusted together in the same tubo. facture, it has never come into extensive use. Metallic stuffing-box packing would be a great boon, provided it answered its purpose. Mr. John Penn used to have one of his small shop engines fitted with metallic stuffing box packing, and the author believes he has so now.

(To be continued.)

The Vielle-Montague Zinc Mines and Foundries Company increased its production of zinc last year to 43,056 tons, as compared with 49,216 tons in 1868, 36,260 tons in 1867, 31,722 tons in 1866, and 30,592 tons in 1865.

It is rarely that we can find a good one in the op-
ticians' stores, but they are so easily monnted that
any working optician could put one together at
short notice. One of our friends made a remark-
ably efficient instrument of this kind, having
formed the lenses of plate glass (a piece of broken
store window), which consequently did not require
the plane side to be ground, and arranged the
lenses in a tube made of stout writing-paper,
pasted. Suitable lenses could, no doubt, be pro-
cured by mail from most opticians, and it would
no doubt require no great manual dexterity to
mount them.

I am not aware of any other considerations than those just adduced which offer even the glimpse of an explanation of the origin of these animal traits in man. We need not, however, confine our attention to idiots only. Whence come the savage snarl, the destructive disposition, the obscene language, the wild howl, the offensive habits, displayed by some of the insane? Why should a human being deprived of his reason ever become so brutal in character as some do, unless he has the brute nature within him? In most large asylums there is one, or more than one, example of a demented person who truly ruminates: bolting his food rapidly, he retires afterwards to a corner, where at his leisure he quietly brings it up again into the mouth and masticates it as the cow does. I should take up a long time if I were to enumerate the various brute-like characteristics that are at times witnessed among the insane ; enough to say that some very strong facts and arguments in support of Mr. Darwin's views might be drawn from the field of morbid psychology. We may, without much difficulty, trace savagery in civilisation, as we can trace animalism in savagery;. and in the degeneration of insanity, in the unkinding, so to say, of the human kind, there are exhibited marks denoting the elementary instincts of its composition.

It behoves us, as scientific inquirers, to realise distinctly the physical meaning of the progress of human intelligence from generation to generation. What structural differences in the brain are implied by it? That an increasing purpose runs through the ages, and that "the thoughts of men are widening with the process of the suns," no one will call in question; and that this process has been accompanied by a progressive development of the cerebral hemispheres, the convolutious of which have increased in size, number, and complexity, will hardly now be disputed. Whether the fragments of ancient human crania which have been discovered in Europe do or do not testify to the existence of a barbarons race that disappeared before historical time, they certainly mark a race not higher than the lowest surviving human variety. Dr. Prichard's comparison of the skulls of the same nation at different periods of its history led him to the conclusion that the present inhabitants of Britain," either as the result of many ages of great intellectual cultivation, or from some other cause, have much more capacious brain-cases than their forefathers." Yet stronger evidence of a growth of brain with the growth of intelligence is furnished by an exami

Two lectures delivered at the Royal College of F.R.C.P., Professor of Medical Jurisprudence in UniPhysicians in 1870. By HENRY MAUDSLEY, M.D., versity College, London.

nous forms."

nation of the brains of existing savages. Gratiolet truly the heirs of the ages. Take the moral If we were to examine the surface of a tool that has figured and described the brains of the Hot- sense, and examine the actions which it sinctions has just been removed from a grindstone, under tentot Venus, who was nowise an idiot. He found and those which it forbids, and thus analyse, or, the lenses of a powerful microscope, it would a striking simplicity and a regular arrangement as it were, decompose, its nature, and it will be appear, as it were, like the rough surface of a of the convolutions of the frontal lobes, which found that the actions which it sanctions are field which has recently been scarified with some presented an almost perfect symmetry in the those which may be proved by sober reason to be implement which formed alternate ridges and two hemispheres, involuntarily recalling the regn- conducive to the well-being and the progress of furrows. Hence, as these ridges and furrows larity and symmetry of the cerebral convolutions the race, and that its prohibitions fall upon the run together from both sides, at the cutting edge, in the lower animals. The brain was palpably actions which, if freely indulged in, would lead to the newly-ground edge seems to be formed of a inferior to that of a normally developed white the degeneration, if not extinction, of mankind. system of minute teeth, rather than to consist of woman, and could only be compared with the And if we could imagine the human race to live a smooth edge. For this reason, a tool is first brain of a white idiotic from arrest of cerebral back again to its earliest infancy-to go back- ground on a coarse stone, so as to wear the surdevelopment. Mr. Marshall has also recently wards through all the scenes and experiences face of the steel away rapidly; then it is polished examined the brain of a Bushwoman, and has through which it has gone forward to its present on a wheel of much finer grit; and finally, in discovered like evidence of structural inferiority: height-and to give back from its mind and order to reduce the serrature as much as possible, the primary convolutions, although all present, character at each time and circumstance, as it a whetstone of the finest grit must be employed. were smaller and much less complicated than in passed it, exactly that which it gained when it This gives a cutting edge having the smallest the European; external connecting convolutions was there before,-should we not find the frag-possible serration. A razor, for example, does were still more remarkably defective; the second- ments and exuvia of the moral sense lying here not have a perfect cutting edge, as one may perary sulci and convolutions were every where and there along the retrogide path, and a condi- ceive by viewing it through a microscope. And decidedly less developed; there was a deficiency tion at the beginning which, whether simian or yet the serrations are actually so much smaller of transverse commissural fibres; and in size, and human, was bare of all true moral feeling? than a human hair that the minute teeth cut the every one of the signs of comparitive inferiority, We are daily witnesses of, and our daily actions hair in twain; but when the serrations on the "it leaned, as it were, to the higher quadrum- testify to, the operation of that plastic law of edge of the razor becomes so battered up and dull The developmental differences nervous organisation by which separate and that they will not sever a hair, or cut a man's between this brain and the brain of a European successive acquisitions are combined and so inti- beard off, the edge must be honed and strapped were in fact of the same kind as, though less in mately blended as to constitute apparently a until the system of minute teeth will be so much degree than, those between the brain of an ape single and undecomposable faculty: we observe smaller than a hair that several of them will take and that of man. Among Europeans the average it in the formation of our volitions; and we ob- hold of the smallest hair at once. These sugweight of the brain is greater in educated than in serve it, in a more simple and less disputable gestions will furnish something of an idea of the uneducated persons; its size-other circumstances form, in the way in which combinations of move-operation in grinding and whetting edge tools. being equal-bearing a general relation to the meats that have been slowly formed by practice Beginners are sometimes instructed, when mental power of the individual. Dr. Thurnam con- are effected finally as easily as if they were a grinding edge tools, to have the stone revolve cludes, from a series of carefully-compiled tables, single and simple movement. If the moral sense towards the cutting edge, and sometimes from it. that while the average weight of the brain in which is derived, then, insomuch as it has been When the first grinding is being done it is a matordinary Europeans is 49 ounces, it is 54-6 ounces acquired in the process of human development ter of indifference whether this is done or not; in distinguished men; and Professor Wagner through the ages-were not more or less innate but when the finishing touches are applied near found a remarkably complex arrangement of the in the well-born individual of this age, if he were and at the very edge, a grinder can always comconvolutions in the brains of five very eminent obliged to go, as the generations of his forefathers ptete his task with more accuracy if the periphery men which he examined. Thus, then, while we have gone, through the elementary process of of the grindstone revolves towards the cutting take it to be well established that the convolutions acquiring it, he would be very much in the posi-edge, as the steel that is worn away will be reof the human brain have undergone a considerable tion of a person who, on each occasion of writing moved more easily; whereas, when a stone runs development through the ages, we may no less his name, had to go through the elementary steps in the opposite direction, the grinder cannot justly conclude that its larger, more numerous, of learning to do so. The progressive evolution always tell exactly when the side of the tool is and complex convolutions reproduce the higher of the human brain is a proof that we do inherit fully ground up to the edge. This is more espe and more varied mental activity to the progressive as a natural endowment the laboured acquisitions cially true when the steel has a rather low or soft evolution of which their progressive increase has of our ancestors; the added structure represents, answered--that they manifest the kind of function as it were, the embodied experience and memories which has determined the structure. The vesicu- of the race; and there is no greater difficulty in lar neurine has increased in quantity and in believing that the moral sense may have been so quality, and the function of the increased and formed, that in believing, what has long been more highly-endowed structure is to display that known and is admitted on all hands, that the intelligence which it unconsciously embodies. young fox or young dog inherits as an instinct The native Australian, who is one of the lowest the special cunning which the foxes and the dogs existing savages, has no words in his language that have gone before it have had to win by hard to express such exalted ideas as justice, love, virtue experience. mercy; he has no such ideas iu his mind, and These remarks are not an unnecessary digros-THE advantages claimed for Mr. Watson's system of obtaining water or other fluids from cannot comprehend them. The vesicular neu- sion. Nor will they have been made in vain if any depth, over any other method, will be easily rine which should embody them in its constitu- they serve to fix in our minds the conviction understood by our scientific readers from the action and manifest them in all its function, has not that the law of progressive evolution and speciali-companying cuts, with but little explanation of been developed in his convolutions; he is as in-sation of nerve-centres, which may be traced the details; its utility in boring through a hard capable, therefore, of the higher mental displays generally from the first appearance of nerve- or rocky soil being more particularly prominent. of abstract reasoning and moral feeling as an tissue in the lowest animals to the complex In sinking or boring by this method, in ordiidiot is, and for a like reason. Indeed, were we structure of the nervous system of man, and nary cases, the first length of tubing is provided to imagine a person born in this country, at this specially from the rudimentary appearance of with a fluted steel penetrator, having a groove cut time, with a brain of no higher development cerebral convolutions to the numerous and com- in the part fitting into the tube, so as to allow it than the brain of an Australian savage or a Bush-plex convolutions of the human brain, does not to revolve on the screws in the lower end of the man, it is perfectly certain that he would be more pipe, which is made stronger for the purpose. The or less of an imbecile. And the only way, I supspindle for carrying the weights used in driving pose, in which beings of so low an order of dedown is provided with a collar, the lower side of velopment could be raised to a civilised level of which forms a fair surface to fall on to the brass feeling and thought would be by cultivation conhand nut, which is screwed on to the upper end of tinued through several generations; they would the tube, so that it is not injured by the blow, and have to undergo a gradual process of humanisa. when down to the surface of the soil this nut is tion before they could attain to the capacity of removed and another length of tube connected civilisation. with an ordinary socket joint, as shown inthe cut, the process being continued as before, and tubes added as required. In boring through a rocky soil a double tube is used; the outer tube at its lower end has a steel collar fluted on the outside, and also revolving at each blow of the weights in a similar manner to that in the foregoing.

abruptly cease its action at the vesicular neurine of the hemispheres, but continues in force within the intimate recesses of the mental organisation. Moreover, they are specially to the purpose, seeing that they enable us to understand in some sort how it is that a perversion or destruction of the moral sense is often one of the earliest symptoms of mental derangement: as the latest and most exquisite product of mental Seme who one moment own freely the broad organisation, the highest bloom of culture, it is truth that all mental manifestations take place the first to testify to disorder of the mindthrough the brain, go on, nevertheless, to straight- centres. Not that we can detect any structural way deny that the conscience or moral sensibility change in such case; it is far too delicate for can be a function of organisation. But if all that. The wonder would, indeed, be if we could mental operations are not in this world equally discover such more than microscopical changes functions of organisation, I know not what war with the instruments of research which we yet rant we have for declaring any to be so. The possess. We might almost as well look to solution of the much-vexed question concerning discover the anatomy of a guat with a telethe origin of the moral sense seems to lie in the scope. considerations just adduced. Are not, indeed, our moral intuitions results of the operation of the fundamental law of nervous organisation by which that which is consciously acquired becomes an unconscious endowment, and is then transmitted as more or less of an instinct to the next ness were a large plane employed, in which were generation? They are examples of knowledge set a hundred or more very small gouges, each which has been hardly gained through the suf- cutting a narrow groove. The sharp grit of the fering and experience of the race being now in- grindstone being harder than the iron or steel, herited as a natural or instinctive sensibility of cuts very small channels in the surface of the the well-constituted brain of the individual. In metal, and the revolving disc carries away all the the matter of our moral feelings we are most minute particles that are detached by the grit.

(To be continued.)

GRINDING EDGE TOOLS.

IDGE tools are fitted up by grinding, very

EDGE
much as a plank would be reduced in thick-

temper. The stone, when running from the edge, will not sweep away every particle of the metal that hangs as a "feather" but when the stone revolves towards the edge there will be no "feather edge" to deceive the eye of the grinder.

WATSON'S DEEP TUBULAR WELLS. (Illustrated on next page.)

The inner ube is provided with a steel point likewise constructed to revolve, as in the first instance of the single penetrator, but has, in addition, two recesses to suit the two catches or tumblers fitted in the revolving collar of the outer tube, which keep it in its proper position, without impeding its withdrawal when necessary. The two tubes are of equal lengths, fitted with brass hand-nuts at the upper ends, similar to that on the single tube, thus insuring their being driven equally together. The inner tube can be drawn to the surface at any time, either for the purpose of being sharpened, or of ascertaining the nature of the soil, &c., and replaced with perfect ease; but in tubes of 3in. or more in diameter, provisioncan

276

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be made for ascertaining the nature of the various strata the tube is passing through without removing the inner tube at all. Where the outer tube is found to be at a sufficient depth to insure a good supply of water, the inner tube is withdrawn. The valves, pump, bucket, and gear are then placed in position-usually about 20ft. from the surface of the water-the pump rod being made hollow, so that in the event of grit or sand interfering with the proper working of the valves water can be passed down it on to them, and the obstruction cleared away-though this will be but seldom required, the pump being provided with a head valve, which always retains a column of water after it is discharged by the pump bucket. The whole of this arrangement will be clearly understood from the engraving, it being a very compact and serviceable job.

These wells are well adapted for the colonies, tropical climates, farms, gold and other mines, also in testing for mineral and other substances, and can be used to advantage as boring tools in Artesian well making.

For mansions situate at any distance from the water the tube wells are found useful.

These pumps are now being constructed for the patentee, Mr. G. Watson, of Plaistow, by Messrs. T. Blundell and Sons, of West India-road, Limehouse.

THE "PHANTOM" BICYCLE.

(For Illustration see page 277). THE machine represented in the accompanying sketch has been the subject of no little controversy among some of our readers, and in placing this cut before them we would recommend those who may desire to have further particulars than we can afford space enough to convey to consult the pages of the interesting pamphlet," The Bicycle; or, the Wheel and the Way," from which we make the following extracts:

"The machine is steered from the middle of the frame, or

from both wheels, and not from the front wheel alone, as in
the ordinary bicycle, and as the front wheel only turns half as
much as usual, it is never brought into proximity even with
the rider's thighs. It is completely railed off too by the frame
In turning a corner, or on a
within which it is exclosed.
curve, each of the wheels are put upon the same are of a
circle; the back wheel, therefore, always follows the line of
the leading wheel; it passes over exactly the same ground, in
fact; there is in consequence no 'drag.' In the event of a
fall the rider does not get hurt by the machine-that is, he
cannot get mixed up or entangled in a painful way between
the front wheel and the backbone, as in the ordinary bicycle.
The shape of the framework ensures greater speed being
obtained than does that of the ordinary pattern. There are
very convenient steps for mounting and dismounting, and
the same contrivances are serviceable as safe and comfortable
rests for the feet. A spring concealed in the steering-socket
destroys the vibratory concussions usually conveyed to the
hands. The cranks are readily adjustable to any length of
Both
throw, and when adjusted' they do not work loose.
the wheels have fixed axles, and run in gun-metal bearings
provided with separate oil cups which do not leak. Lastly,
the wheels are a grand improvement in themselves, being
made upon the suspended principle in such a way that they
act as springs, and assist in dispelling the concussions caused
The general result is that a bicycle is pro-
by rough roads.
duced which is of a decidedly improved appearance, which is
much safer to ride, easier to steer, far less dangerous to fall
from, and which is much easier to mount and dismount.
Finally, the speed, and consequently the case of driving are
improved by at least a third."

The remarks as to india-rubber tires are of general
interest -

"A rubber tire is usually made up smaller than the rim of the wheel it is intended for, and is held in its place by being stretched into a groove, formed in the wheel by putting flanges on each side of the rim. The defects of this plan are that when the wheel is pivoted upon its base, as when the machine is turning a corner, the rubber tire is wrung or twisted by the screwing motion of the wheel upon the ground, and directly a part of it is raised a little above the edge of the flange, the whole of the tire instantly springs out of the groove. To get it back is a job of some difficulty, especially if the accident happens when on a journey, as it takes at least two or three pairs of hands, and some little skill to stretch it in again. The stretching on of the tire is intended to prevent it from being twisted out by making it impossible to stretch it further. This plan not only frequently fails to effect its object in that respect, however, but it exposes the tire to a constant danger of, if possible, a worse kind in another way. Stretched rubber gapes wherever it is cut, and as a very few

weeks' wear, especially in districts where the roads are macadamised, produces a good many cuts in the tire, the result 18 that it is disfigured by a number of ugly gaps, and is drawn up into thick and thin places, instead of being of an even thickness throughout its circumference. It then makes the machine bump and down, and becomes more of a nuisance than an advantage, and by-and-bye the contractile tendency is strong enough in the thick parts to tear the tire completely asunder at one or other of the thin places.

"The rubber tire of the Phantom' is a different thing, however, and it is not liable to any of these disadvantages. The principle upon which the wheel is constructed 'dispenses altogether with the necessity for an iron tire to keep it together, as the rim is held in by the suspending rods; that leaves a wood surface upon which to fix the rubber tire. The latter is made half round, and has a canvas base made up with it in the vulcanising process. The canvas hase serves two purposes; it prevents the tire from stretching in the direction of its length, and it forms a bed for holding the heads of short iron pins, which are driven through the rubber and into the wood rim at intervals of about every inch of the The heads of these pins are buried in the circumference. rubber, which closes over the hole made in driving them in, so that they are not seen or felt in any way. They keep the rubber tire from being shoved off. Then, as the rubber is not, and in fact cannot be, stretched in the direction of its length, it does not gape and stretch wherever it happens to get cut by sharp stones. Consequently there is practically no end to the wear of the tire, as, in spite of the cuts it may have across it, it retains its uniformity of thickness, and there is never any defect in its action. Of course the cutting of the rubber tire cannot be prevented, but by this plan of fixing it on, the practical usefulness and luxurious effect is not diminished by the cutting, the gaping of the cuts being entirely prevented."

TO CLEAN PAINT.-There is a very simple method to clean paint that has become dirty, and if our housewives should adopt it, it would save them a great deal of trouble. Provide a plate with some of the best whiting to be had, and have ready some clean warm water and a piece of flannel, which dip into the water and squeeze nearly dry; then take as much whiting as will adhere to it, apply it to the painted surface, when a little rubbing will instantly remove any dirt or grease. After which, wash the part well with clean water, rubbing it dry with a soft chamois. Paint thus cleaned looks as well as when first laid on, without any injury to the most delicate colours. It is far better than using soap, and does not require more than half the time and labour.

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[We do not hold ourselves responsible for the opinions of our correspondents. The EDITOR respectfully requests that all communications should be drawn up as briefly as possible.]

*.* All communications should be addressed to the EDITOR of the ENGLISH MECHANIC, 31, Tavistockstreet, Covent Garden, W.C.

NEW STYLE OF RAILWAY. that June is, as my querist probably knows, the worst, month of all the twelve for the examination of nebulæ.

he

I may tell "Investigator" (also on p. 256) that the method now universally employed, where practicable, for the determination of longitude, is that by the Electric Telegraph. As appears to possess "Loomis's Practical Astronomy," I can refer him to pp. 35, et seq., of that work for full details of the method adopted in practice. It may, however, serve to show with what extraordinary accuracy longitude can be obtained by the transport of chronometers, if I All eheques and Post Office Orders to be made pay- mention that of Mr. Airy, in 1844, superintended the able to J. PASSMORE EDWARDS. transmission of thirty pocket chronometers ten times backwards and forward between Greenwich and Feagh Main, at Valencia, in the extreme West of Ireland; and that when the difference of longitude between these two places was redetermined galvanically in the summer of 1862, the result was almost precisely identical with

ASTRONOMICAL, OPTICAL, AND GENERAL. SIR,-Let me, imprimis, congratulate my fellow subscribers upon the advent into your columns of our Great Solar Spectroscopist, Mr. J. Norman Lockyer. Let us hope that after the appearance of so convincing a reply from the man, perhaps of all living the best qualified to speak ex cathedrá on this special subject, we shall have no more vague guesses and expressions of doubt from people who are confessedly ignorant of the very elements of the problem which they undertake to discuss.

Lower on the same page (256), I find two or three queries by Mr. H. W. Bishop, towhich I will reply in order. First, then, just as twilight is fading, is the most favourable time to examine the colour of a star. In the case of a star like Sirius, Mr. B. must remember that from its relative proximity to the horizon, atmospheric dispersion operates in tinging it very perceptibly with colour; and th's is exaggerated by its projection on the black background of the midnight sky. Of course, I am supposing the star to be one of a tolerably low magnitude. Some of the minute red stars require the darkest sky you can get, and some little attention to boot, to discern their colour fairly. On the other hand, that lovely pair a Herculis is never seen to such advantage as in full twilight. I must confess my inability to "give the comparative brightness of the chief nebulæ visible in a 3iu. achromatic," because I am unaware of any photometric process which is applicable to such a measurement: but if a rough eye estimation of relative visibility be of any use to your correspondent, I may tell him that of the nebulæ now favourably situated for observation, he ought to see 70 Hersch. I. Virginis, and will have some difficulty with 99 Hersch. I Boötis; while 418 Hersch. II. Boötis, and 756 Hersch. II. Boötis will be beyond his power altogether. 13 Messier Herculis he will either barely resolve, or see as a bright nebula, according to the excellence of his instrument. 57 Messier, the Ring Nebula in Lyra, will, in a firstrate instrument, show traces of luminosity inside of the ring proper. This is all vague enough, but I do not see well how to frame my response differently. Before dismssing this branch of my subject, I may say

THE "PHANTOM" BICYCLE.-(Described on page 276.)

ceiving with the Astronomer Royal that the elliI must, however, add that plicity amounts to 003352. a most elaborate series of investigations, undertaken by Colonel Clarke, of the Engineers, tends to show that the ellipsoid which best represents existing measurements has its major axis (Equatorial) in Longitude 13° 58' 5" E, and that the greatest and least values of the meridian compression are

1

gitude 13° 58′ 5′′ E., and 309-364

1

-in lon286-779

in longitude 103° 58' 5" E

The difference of the Equatorial semi-axes is 5308ft. or, roughly, about a mile. It will hence be seen that the figure of the Earth is by no means absolutely synmetrical, nor even that of any solid of revolution. Finally," Investigator's" references to page 130, &co

are presumably te

those of some volumof the "Nautical Ale manac," but, in the absence of the name of the work to which they pertain, they are just a little vague.

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other

The Welsh Shepherd," p. 256, like numberless people, severely exercises himself about a question upon which as much nonsense, physical and metaphysical, has been talked.. as has been uttered, about most things. The whole matter seems to lie in a nutshell. If, from the way our eyes are placed in the head, we have to raise them to look at a part of an object, we say that that is the top; if we have to depress them to see another part, we call that the bottom. Our whole notion of up and down is derived from motion; and if the imupon the age fell stomach instead of the retina, and we had to raise our body to perceive it, we should say that that part was the highest; if, on the other hand, the body had to be lowered, we should call the part of the image which necessitated such lowering for its perception the lowest. The socalled "inverted image on the retina, is treated by most people as though, so to speak, we saw that; albeit to do so, we should have to have another eye

behind it!

What, in the name of fortune, does "F. W. M." (p. 257), imagine he is adding to a controversy which has been carried on usque ad nauseam, by reiterating what has been said over and over and over again about the Earth and Moon forming parts of one solid globe?

FELLOW OF THE ROYAL ASTRONOMICAL SOCIETY.

that obtained by the older method. Moon Culminating Stars, unless observations be very much multiplied and great care be taken to observe both limbs of the moon, give but indifferent results, and Lunar distances, even in the hands of skilled observers, are only pretty good; but Occultations of Fixed Stars by the Moon when carefully observed, and rigidly reduced, are very much better still. Secondly, every visible Occultation is observed at Greenwich, as are the phenomena of Jupiter's Satellites &c. These are published at intervals in the "Monthly Notices of the Royal Astronomical Society"; and this answers your correspondent's third query as well. Next, all the observations at Greenwich of the Moon, NEW STYLE OF RAILWAY. both with the transit circle on the Meridian, and with the altazimuth off it, are "for the purpose of detecting SIR,-I send you a drawing of a new style of railIt runs on one rait errors of the lunar tables." The Greenwich observa- way just introduced into Lisbon. tions are published by John Murray, of Albemarle-along the common thoroughfare. In the illustration street, London. With regard to the immediately fol- you see that the engine and carriages have small lowing question, he may take the length of the Polar wheels, which run on the rail, and large ones on the The cylinders are under the boiler, just like semi-axis of the Earth at 20853768ft., and that of the road. equatorial semi-axis he may deduce from it by con- any other engine. The wheel which the man in front

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