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the finger of demonstration, inscribes the name of one God on the altar of the universe.

Now let us consider, shortly, how this continuity of matter, and this universality of the laws which govern it is established.

The stars, called fixed, are not, in reality, fixed; they all move in a certain given direction through space, with a motion which will eventually mingle the constellations. The 61st star, for instance, of the constellation called the Swan, is ascertained to move in a straight line over five-seconds of the heavens annually; and, by the observations of Messrs. Mathiou and Arago, it appears that this star cannot certainly be distant from us less than 412,000 times the diameter of the earth’s orbit; that is 412,000 times 39,000,000 of leagues. Now, if we suppose it to be at this distance, its motion through the heavens could not appear to us to be five seconds annually, unless it actually travelled through a space of 8 millions of millions of leagues in that time. This is one of those stars which, but as yesterday, were called fixed stars. But a motion of the whole host of heaven, as with one common consent, and in one common direction through interminable space, is not the only motion which the astronomer sees amongst them: there are stars which revolve round one another.

When first telescopes of any considerable power came to be made, it was discovered that certain stars which appeared to the naked eye to be single, when seen through these telescopes, resolved themselves into two, and these were called double stars. Stars of this kind have since been ascertained to be very numerous; and groups have been found not only of two but of three and four stars. Of 120,000 stars examined, to ascertain whether they were multiple stars or not, 3057, or about one in forty, were found to be so; and were our telescopes sufficiently good, it is possible, if not probable, that all the stars which appear to us single would resolve themselves into systems or groups.

Of the stars of which these groups are composed, one is always found greatly to exceed the rest in splendour. It was imagined at first, that this difference of brilliancy resulted from a great difference of distance; and did this difference of distance exist, it would offer a means of ascertaining the parallax, and therefore the actual distance of the whole group. Under this impression, Sir William Herschel undertook a series of observations at Slough, hoping to discover a parallactic motion in the stars; and, as continually happens, if people would but acknowledge it, in seeking for one thing he found another.

He discovered that, almost in every case, groups of multiple stars, of unequal magnitude, were not, as had hitherto been supposed, bodies isolated and independent of one another, placed by chance, so that lines drawn from them to the eye nearly coincided, but that they are systems, of which the greatest of the group is the central and controlling mass, round which the lesser stars of the group continually revolved, as do the planets of our system round the central sun.

In a group of two, for instance, the lesser star will sometimes be seen to the east, at another in the west, or to the north or south of the greater star. Here, then, is a direct verification of those speculations on the plurality of worlds, which have so long occupied the attention of men of inquisitive minds. Here are systems peopling the whole of space,

areas.

which revolve round one another as do the bodies of that system of which the planet on which we live forms a part. But is this analogy complete? There are certain peculiar laws which govern the motions of the planets which compose our system, indicating, demonstratively, the nature of the force by which they are impelled towards their common centre. These laws are very remarkable; they are called Kepler's laws: one of them is, an imaginary line being drawn from any planet of our system to the sun, although each such planet moves not in a circle but in an ellipse or oval, and not with the same constant velocity, but with a velocity continually varying; yet the space over which the line spoken of sweeps, in a given time, say a week, in any one portion, is the same as that over which it sweeps in any other: this is called the law of the equal description of

Another of Kepler's laws is this: The larger axis of the ellipse being called its axis major, the periodic times of the different planets of our system are to one another in the ratio of the square roots of the cubes of these axes majores. These two laws depend upon the fact, that the planets and sun attract and are attracted by one another.

If then we find among these distant groups or systems of suns, the same equal description of areas, and the same ratio of periodic times, we conclude that the stars of each system attract one another, and that the forces by which they are attracted vary inversely as the squares of the distances, and are therefore similar to gravity; and, lastly, that motion is there governed by the same laws as here. Now we do find this to be the case. The motions of double stars have been very accurately observed, among others, by Sir J. Herschel, and he has ascertained that their motion is subject to these laws. He has accurately determined the periodic times, the axes majores, and eccentricities of eight of them; and in every respect does he find the relations which exist between the planetary motions to obtain among the bodies which compose these far remote systems. What then, is the conclusion, but that all these multiplied and isolated systems which people space, and of which the universe is the aggregate, are subject to the same laws of motion and of force as obtain here. Thus the laws of gravitation and motion, which Newton showed to embrace at once the fall of bodies at the earth's surface, and the phenomena of our planetary system, must be extended to the region of the fixed stars. With us, all matter is crowded ith life, every interstice in it is but the habitat of some organized living agent; or the space wherein some form of vegetable life develops itself. Now, the matter of the planetary bodies is analogous to ours in every other respect, why not in this too!--that it is the appointed dwelling-place of organized living beings. And if of the subordinate classes of these, why not of intelligent living beings? Surely, in the absence of all evidence of an opposite state of things, we are bound to conclude, by far the most probable supposition to be, that our planet, which is in every other respect a sample of the other bodies of our system, resembles them in this also; they, as well as ourselves, have their day and night, their summer and their winter; why, as with us, should not these changes be coupled with the phenomena of animal and vegetable life? What a prodigious field of speculation is thus opened to our view. Mercury, for instance, completes his year in about one quarter of ours, and he receives about seven times as much heat from

the sun.

What then is the vegetation, and what the class of living beings, suited to this rapid change of seasons, and glowing temperature ? Jupiter's year is nearly twelve of ours, and each of his seasons is thus three years in length; what gigantic vegetation is that which goes through this toilsome period of change. His day is about ten hours long: what developement of animal life is that whose periods of repose come more than twice as frequently as our own? Four bright moons illumine the short night of this planet: why is this short period of repose brightened almost into daylight?

But if it be by far the most probable of these hypotheses, to suppose that the planets of our own system, because of the analogy they bear in other respects to our own planet, display with it the wonders of animal and vegetable creation; then must the planetary systems, which unquestionably surround the stars, too, having a direct analogy to those of our system, be admitted to be, like them, but the means, but the agents, in the dissemination of life through all space; thus all the boundless fields through which the stars of heaven take their course, are peopled with beings, who bow before God in speechless thanksgiving for the enjoyment of the blessings of life; or whose privilege it is to offer to him the incense of reason and of the understanding.

The subject is overwhelming in its sublimity; let us, however, yet pursue it one step further. One or both of the stars, composing each multiple system, shine not with white, but with coloured light; and their colours are for the most part different; every variety of colour is found, but the prevailing colours are blue, and green, and yellow; these facts have been examined with great care, and may be considered as established. Now, what are the phenomena to which these different colours of their double or triple groups of suns must give to the systems of planets by which each group is, beyond all doubt, accompanied; three different coloured suns at once, or alternately, traversing their skies,-days of green light, of blue light, of yellow light succeeding each other, or blending their hues,--seasons in which these colours alternately prevail. These are speculations in which the imagination exhausts itself.

In the course of this introduction, I have on more than one occasion spoken of the truths of Natural Science, with a direct reference to the wisdom, the power, and the goodness of the Author of Nature. I have done this advisedly, and from a belief, that were it not an impiety to discuss the manifestations of infinite wisdom and goodness in created things, otherwise than with sentiments of gratitude to the Creator, and deep humility before him, it could at best be considered but as an affectation, or a folly. It is impossible to consider that instruction complete, which having for its object the developement of the relation of cause and effect in those portions of the sequence of natural things which lie within the scope of sensation, does not point out their dependence upon that First Cause which is beyond it. The study of Natural Philosophy and Natural Theology, if rightly pursued, are one; and true Science but a perpetual worship of God in the firmament of his power.

ON THE MANUFACTURE OF POLISHED STEEL STUDS

AND BEADS. BY THOMAS GILL.

THESE studs and beads are employed in great quantities by the steelworkers, by the makers of steel dress sword-hilts, and in what the French term bijouterie en acier, or steel jewellery, of which we shall treat hereafter; they, therefore, form manufactures of considerable importance, but we believe, they have not hitherto been described by any writer.

The best Steel Studs are made out of decarbonated cast-steel; the commoner kinds are cut out of sheet-iron, of a proper thickness, and are formed into small round or oval pieces, by beds and punches, in the screw-press, in the usual and well-known manner, and which, therefore, need not be described here. Each piece has, afterwards, a hole made partly through the middle of it, at its back, by means of a pointed steelpunch and hammer, to receive a stem of pointed iron-wire, which is driven hard into it, to retain it in its place, until it is afterwards secured more firmly by soldering. The appearance of them in this state will be

similar to those shown in fig. 1, which is an edge-view, or Fig. 1.

section, and a plan of one of them. A number of these studs, thus prepared, are then enclosed in wetted brown

or rope-paper, together with bits of brass, as solder, and a little borax, as a flux, and the whole wrapped up into a cylindrical shape ; this is then covered with a crust of clay, leaving, however, a small hole at one end of it open, for a purpose to be hereafter described. It is then placed in a forge fire, gradually and carefully heated by blowing, and, at the same time, turned round a little, from time to time, until a white fume or vapour is seen to issue from the hole previously made for that purpose; this indicates that the brass is fused, the zinc becoming volatilized in its usual form, and thus escaping : the mass is then to be instantly withdrawn from the fire, and to be rolled backwards and forwards upon the ground, so as to diffuse the solder uniformly amongst the studs, whilst cooling. And here, it may be remarked, that the zinc in the brass, which rendered it more fusible, becoming thus volatilized, leaves behind it chiefly the copper with which it was combined to make brass; and it is well known, that copper

forms an intimate

and ose union with iron, when thus heated in contact with it, and oxygen nearly excluded. When cold, the crust of clay is broken off the mass; and the studs will be found to have their stems of wire firmly soldered to them, and ready to undergo the succeeding process, viz., that of being brought to a proper shape by filing them.

The next process is that of case-hardening them; but, as it is requisite that their stems should remain soft afterwards, in order to admit of being screwed or riveted in use, so it is necessary to prevent the action of the case-hardening materials upon them; this is effected by enclosing each stem in a slight coat of clay, and thus cutting off all access of the carbonaceous materials to them.

Animal charcoal is the material usually employed in case-hardening, by the steel-workers; this is frequently procured from the ammoniaworks, after the distillation of bones, for the production of the different matters to be obtained therefrom. Charcoal is ground to a coarse powder, and put into a sheet-iron or a cast-iron box; a layer of it being spread over the bottom of the box, a number of the studs are then dispersed, at equal distances apart, over that layer of charcoal; another layer of charcoal is then spread over them, and this, in its turn, receives another deposit of the studs; and so on, stratum super stratum, until the box is nearly filled, the uppermost layer being composed of charcoal. The box thus filled, or several of them, must then be placed in an open fire-place, filled with pit-coal, and remain exposed to a red-heat, for a sufficient time, to cause the case-hardening effect to take place, and which will depend upon the size of the articles exposed to its action, or to the depth or thickness to which it is intended to carry the hardening process; it being very desirable, frequently, to limit its action to the exterior surfaces of the articles, leaving their interior still merely soft iron, and this, in order to combine strength or toughness with great hardness, in the delicate, small, and frequently thin articles, made in steel-jewellery. When the case-hardening effect is thought to be sufficiently produced, the whole contents of the box, charcoal and all, are thrown into water, or, which is better, into water the surface of which is covered with a layer of oil, two or three inches in thickness, and which is thought to prevent the liability of the articles cracking in hardening them.

Burnt leather is, by some, preferred to the charcoal of bones, for case-hardening. In order to prepare this, old shoes, or other scraps of leather, are collected, and these are burnt or scorched by being laid upon a fire of pit-coal, made in some open place, away from houses, on account of the ill-smell produced in the burning; the scorching is to be continued until the leather is sufficiently friable to be capable of beating into powder when become cold.

Decarbonated cast-steel is preferred to iron, for delicate works in steel-jewellery, where it is wished to avoid all appearance of flaws or veins in the articles made of it. This process is performed by enclosing the slips, or sheets of cast-steel, in iron boxes, filled with rusty iron-filings, and which are greedy of carbon, and deprive the cast-steel of it; thereby reducing it to the state of the softest and purest iron, when heated to redness during several days and nights, according to the thickness of the steel: thus treated, it will not harden like steel, by merely heating and cooling, but, after forming the articles of it, they must be case-hardened, as above described.

The cutting and polishing facets, on steel studs, is performed in a nearly similar manner to those upon steel-beads; and we shall, therefore, postpone the description thereof, until we have treated of the manufacture of these latter articles.

Steel Beads, if very small, are cut out of thick sheet-iron, or decarbonated cast-steel, by means of beds and punches, in the screw-press, as in the making of steel studs, but have holes perforated entirely through them. If, however, they are of larger sizes, then they require a different treatment; being formed hollow, out of decarbonated cast-steel, in the following very ingenious manner:—The steel, being cut into circular peces, by means of beds and punches, in the screw-press, is next to be dishd, or made concave, in a pair of dies, fitted concave and convex to each oher, in a screw-press, until they have rims turned up around them,

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