of five hundred and seventy 12-pounders | likely that the breech-loading apparatus will in service, thirteen have been returned for re- be dispensed with altogether in future, as Sir pairs, of which only three have been pro- William Armstrong in his large guns has nounced unserviceable and the remainder re-adopted what he calls the "shunt-loading pairable at an inconsiderable expense. The or muzzle-loading principle, thus returning 12-pounders are field-guns and have been to the identical gun from which he took all used in the China and New Zealand cam- his successful ideas-the Treadwell patent. paigns with great success. The heavy cast- The gun is not so strong as the cast-iron iron guns in the British navy have in a great gun in its transverse axis. A 6-pounder measure been laid aside and their places supplied with Armstrong 110-pounders breech loaders, which are the largest guns yet in service-the 150, 300, and 600 muzzle-loaders being as yet experimental. Sir William Armstrong reports that of all the guns made by him, or at the Government workshops on his plan, not one has burst, nor has one been destroyed except by the gradual process. To meet the charge that the guns are too delicate to bear shipment, it is reported by the Master of Ordnance that at the Peiho Forts in China, in New Zealand and Bengal, the guns came out of the ships' holds in perfect order and ready for use.

The disadvantages or weaknesses of the Armstrong gun are: the vent-pieces are troublesome and cumbrous; the lifting out and replacing to load occupy time, and there is liability to leakage of gas at the breech. As the gun increases in size, the vent-piece has to be increased proportionally till, with the 300-pounder gun, a separate machinery for lifting will have to be introduced '(if this gun is made breech loading), as the vent-piece will weigh nearly a thousand pounds. With the large guns and very heavy charges of powder the vent-piece is not unfrequently. broken, and a spare one accompanies each gun. The machinery for forcing up the ventpiece is complex and in action liable to disarrangement by the accident of an enemy's shot, or violent recoil. In point of fact it is quite *The "gradual process," mentioned by Sir William Armstrong, is probably what is known to practical gunners as the lodgment or indentation of the ball. This first shows itself at the point immediately under the ball where it rests at the moment of the discharge. It is best observed in a soft bronze or wrought iron gun, and from the first instant of its appearance, as a slight impression of the under surface of the ball, it goes on increasing at every discharge until it becomes so deep as to deflect the ball upwards at the instant of its flight to strike the upper surface of the bore, where a second indentation takes place, considerably in advance of the first, and from this a third still more advanced upon the under side. These indentations go on in. creasing in size and number, and at length bulges appear upon the outside of the gun, which becomes oval near the muzzle and at last is destroyed.

pounder Armstrong at right angles to its bronze gun was brought up against a 12length. Three shots were fired; the first struck about eighteen inches back from the muzzle, and perceptibly deflected it from the right line; the second struck half-way be tween the muzzle and trunnions, and deflected over thirty degrees; the third struck behind the trunnions, and completed the destruction. The distance between the guns in this trial was thirty yards.

The 110-pounder is not so effective a gun for heavy pounding at short range as the 68poundef cast-iron gun. The 68-pounder, with a charge of sixteen pounds of powder, gives an initial velocity to the ball of about two thousand feet a second; the 110-pounder but then the range of the Armstrong is vastly Armstrong thirteen hundred feet a second; superior to the cast-iron, and while the former appears capable of almost indefinite expansion as to size of bore and weight of projectile, the 68-pounder seems to be the limit of the power of the cast-iron.

The recoil of the Armstrong gun is great, but not excessive as stated.

The matter of the excessive cost of the guns may be set at rest by the acknowledged fact that the gun which will do the most work is cheapest, whatever it may cost. The cost of repair, as before mentioned, is slight.

To sum up, therefore, it would appear that, aside from the breech-loading apparatus (which will doubtless be abandoned altogether), the Armstrong gun is very much more of a success than is generally supposed. When the present series of experiments is concluded, England will be able to take the field with 300, 600, and 1000-pounder muzzle-loading guns, which can be safely fired with heavy charges of powder, and can we say as much? It is certainly little creditable to us to laugh so loudly at our neighbors' supposed mishaps, considering the lamentable failure of our Rodman 15-inch guns and Parrott 300-pounders. * While we continue to arm our monitors with cast-iron abortions that even the Turks (whose ideas our Ordnance Board seem to have borrowed) would be ashamed of, it is not becoming in us to laugh at others.

W.

Nearly all the 300-pounder Parrott guns used at the siege of Charleston are said to have burst at the first discharge.

POETRY.-Far Away, 386. Mists, 386. A Christmas Carol, 386. Suspiria Ensis, 431. The Diamond, 432. The Southern Church, 432. Baby Marguerite, 432. Marching Song of the First of Arkansas, 432.

SHORT ARTICLES.-Mr. Thackeray, 401. Literary Intelligence, 401. Death of the King of Prussia's Head Gardener, 412. British Almanack and Companion for 1864, 415. The Will of Mrs. Willyams, 417. Federal Progress Map, 417. Miles O'Reilly on the Naygurs, 427. Relics from Pompeii, 427. Literary, 427. Chinese Crucifixion, 430.

NEW YEAR'S PRESENTS TO CLERGYMEN.-Our text will be found on the front of several of the late Nos.; but we now ask our readers to apply it to a single class of persons, while the price of every article of food or clothing, and of all the necessaries of life (excepting The Living Age), has been increased, little or nothing has been done to raise proportionally the salaries of clergymen. They are obliged to lessen their comforts, in order to meet this pressure.

Reader, if you wish to refresh the mind and the heart of the man who "ministers to you in holy things," present him with mental food once a week, and do not give him The Living Age if there be any other work that will do him more good.

ADVANCE IN THE PRICE OF BINDING.-The Covers for The Living Age are made up of Cotton Cloth and Pasteboard; and the manufacturers advanced their prices-nearly doubled themsome time ago. We ought then to have increased our charge for binding, but neglected to do so. But for all Volumes bound by us after the 15th of March, the price will be sixty-five cents.

PUBLISHED EVERY SATURDAY BY

LITTELL, SON, & CO.,
30 BROMFIELD STREET, BOSTON.

For Six Dollars a year, in advance, remitted directly to the Publishers, the LIVING AGE will be punctually forwarded free of postage.

Complete sets of the First Series, in thirty-six volumes, and of the Second Series, in twenty volumes handsomely bound, packed in neat boxes, and delivered in all the principal cities, free of expense of freight, are for sale at two dollars a volume.

ANY VOLUME may be had separately, at two dollars, bound, or a dollar and a half in numbers.

ANY NUMBER may be had for 13 cents; and it is well worth while for subscribers or purchasers to com-plete any broken volumes they may have, and thus greatly enhance their value.

From The Edinburgh Review.

1. Heat considered as a Mode of Motion; being a Course of Twelve Lectures delivered at the Royal Institution of Great Britain in the Season of 1862. By John Tyndall,

F.R.S. London: 1863.

2. On the Mechanical Equivalent of Heat. By J. P. Joule, LL.D., F.R.S. "Philosophical Transactions," 1850, Part I. p. 61. London.

66

66

is equivalent to or may be made to produce a given quantity of another form. The mechanical theory of heat declares that heat has no existence independently of matter--that what we call heat is only a peculiar condition of matter, viz., "a vibration of its ultimate particles: so that, as heat is nothing but motion, we can measure heat, as we measure common mechanical energy, by a weight falling through a given space. Nor is this all that this "New Philosophy," as Professor Tyndall rightly calls it, teaches us; for it further shows by virtue of the convertibility of these "imponderables," as they have been termed, and owing to the possibility of expressing each of these in terms of common mechanics, that the destruction or creation of energy in the world is just as impossible as the creation or destruction of matter itself. In the history of physical science, as in the history of nations, sudden revolutions mark great events which stand out conspicuous above the ordinary quiet progress of the day. Such a revolution was effected in the world of science by Lavoisier's introduction of the balance into chemistry, for it thereby became evident that man can neither create nor destroy matter; so that, for instance when a candle burns, the substance of the candle is not lost or destroyed, but has simply become insensible to our powers of vision. A second and equally important revolution in science has recently been effected by the adoption of the New Philosophy of the Mechanical Theory of Heat, experimentally founded, as we shall see, by Dr. Joule of Manchester, on the leading principle of the "Conservation and Indestructibility of Energy."

3. On Celestial Dynamics. By Dr. J. R. Mayer, of Heilbronn. Philosophical Magazine," 4th Series, Vol. XXV. P. 241. London, Dublin, and Edinburgh. MR. SMILES relates, in his Lives of the Engineers, that George Stephenson one day said to Dr. Buckland, as a train passed in front of Tapton House, "Now, Buckland, I have a poser for you. Can you tell me what is the power that is driving that train ?” “ Well," said the other, 6. I suppose it is one of your big engines." "But what drives the engine? “Oh, very likely a canny Newcastle driver." "What do you say to the light of the sun? "How can that be?" asked the doctor. "It is nothing else," said the engineer; "it is light bottled up in the carth for tens of thousands of years-light absorbed by plants and vegetables, being necessary for the condensation of carbon during the process of their growth; and now, after being buried in the earth for long ages in fields of coal, that latent light is again brought forth and liberated, made to work, as in that locomotive, for great human purposes. This observation, made by the father of the railroad system, strange though it may at first sight appear, is literally accurate: it is an ingenious deduction from a grand expression of Nature's truth lately perceived by scientific men, and In order that we may understand the full now known under the name of the "Mechan- meaning and appreciate the wide scope of ical or Dynamical Theory of Heat." This this grand principle, we must proceed to contheory is not merely valuable as giving us sider some of the fundamental experiments correct views of the nature of this all-pervad-upon which this most recent of the brilliant ing and life-sustaining principle of heat, it results of modern science is based; rememlikewise leads to the discovery of a far wider | bering that it is only from "questions thus and more important set of truths, all tending put to Nature" that we can hope to gain any to the conclusion that the great agencies knowledge of her secrets. Heat, Light, Electricity, Magnetism—which uphold life and produce such colossal changes on our globe-are but the expressions in different languages of one great power; that these various forms of energy are mutually convertible; that we can express any one of them in the terms of any other; and, therefore, that a certain quantity of the one form

The first branch of science in which the principle of the conservation of energy became apparent is mechanics; and it has long been well known that labor cannot be effected without a corresponding expenditure of mechanical energy. The "mechanical powers," as they are termed, are simply means for transferring labor into any wished

for channel. No augmentation of labor can | chine which will produce mechanical effect be effected by them; for, although by means without any corresponding or equivalent exof a small weight at the long end of a lever penditure of labor, and thus attain the greatly we can raise a heavier weight, say a weight desired end of making something out of nothten times as large, placed at the other end, ing? In fact, have we not such a machine the space through which the small weight in the steam-engine? Where are we to find must pass is at least ten times as great as in this machine the expenditure of labor that through which the heavy weight is equivalent to the work done? In the waterraised; and hence there is clearly no aug- wheel we have, in the descending water, an mentation of power. The true expression of evident mechanical equivalent for the work the power exerted is invariably the weight done; but in the steam-engine, if the condenmultiplied into the distance through which sation were perfect, we may imagine that the it falls. This is called the "laboring force" position of all parts of the machine, and of -the force which produces results, which the water used for the production of steam, overcomes resistance; and the great principle is precisely the same at the end as it was at in mechanics is expressed in the maintenance the beginning of the stroke of the piston. of this law that by means of any machine no effects can be produced which exceed the laboring force of the motive power. This, then, is the true measure for mechanical work. To raise ten pounds through the space of one foot requires a given expenditure of power; twice that amount of power must be expended in raising it through two feet, and the same amount of power will be required to raise ten pounds through one foot as will be needed to raise one pound through ten feet. Every kind of mechanical work, whether done by machine or animal power, can be represented and measured by weights raised through given spaces; and the unit of measurement and mechanical work is taken to be the weight of one pound raised through the space of one foot. The quantity of mechanical power necessary to effect this work is termed a "footpound."* The principle of the conservation of energy as regards ordinary mechanics was completely and mathematically stated by Newton, and a proof was thus given of the absurdity of the long-sought-for perpetuum mobile at least in mechanical contrivances.

However apparent it may be that action and reaction are equal and opposite in the domain of strictly mechanical forces, the wider application of the same law to the manifestation of the other powers of nature seems by no means so clear. Could we not, it may be asked, by help of heat, electricity, or some such occult force, construct a ma

In almost all scientific works the French stand

ards of weight and length are now employed; and as these units will probably before long come into general use in England, it may be well to remember that the French standard of a kilogramme-metreviz., the weight of a kilogramme raised through the space of one metre-is equal to 7.23 foot-pounds.

To question such as these the new philosophy gives a definite and satisfactory answer, proving, as clearly as Newton did in mechanics, that by the employment of none of the powers of nature can work be done without a corresponding supply of energy of some kind. Thus in the steam-engine we find the source of necessary power in the heat which disappears in the cylinder; the amount of heat which the waste steam conveys into the condenser not being nearly as much as that which enters the cylinder, the difference between the two amounts is converted into mechanical action. So that at last we come to the conclusion that, with whatsoever forces of nature we operate, a perpetuum mobile cannot be constructed-that we cannot by any means whatever produce an effect without a consumption of some kind of power. What follows from this important conclusion? What do we mean when we say that a perpetuum mobile is impossible? We mean that there is no such thing in nature as a creation of force; that all the changes which we see going on around us are produced solely by the transference of force; and hence force cannot be destroyed any more than matter. We may sum up these results in the words of Mr. Grove, an early and able expounder of these views: "In all phenomena, the more closely they are investigated, the more we are convinced that, humanly speaking, neither matter nor force can be created or annihilated, and that an essential cause is unattainable. Causation is the will, creation the act of God."

Although the idea that heat is nothing more than motion has frequently been expressed by various writers even in remote