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tion to Dr. Robson, of Warrington; and Dr. Kendrick, who has watched the discoveries at Wilderspool, promises a full account of them for the next volume of Transactions of the “Historic Society."

The latter part of Mr. Ecroyd Smith's pamphlet is occupied by his report of the archæological produce of THE CHESHIRE COAST during the year 1866, in continuation of a former report, of which we have given an account before (INTELLECTUAL OBSERVER for May, 1867). Of the objects thus found, Mr. Smith has given a classed list, descriptive when necessary, with engravings of a few of the more interesting objects found. Under the head of Primeval, he enumerates twenty-one rudely-fashioned implements of Aint and limestone, an arrow-head of bone, and a curious skewer, or pin, made of whalebone. To the Roman period belong four Roman coins (the only three which are legible belonging to the Emperors Nero, Antoninus Pius, and Probus); a key; a fibula of the bow shape ; an acus, or pin, of a brooch ; two dress pins, or (as they are usually called, perhaps in this case less correctly) hair-pins; and a piece of hæmatite, which Mr. Smith supposes to have been used as an amulet. The Saxon period is only represented in this list by two glass beads, of a pale straw colour. The objects here classed under the head of Early English, and which would perhaps be better described as Medieval, are so numerous and so varied in their material and character that we cannot attempt to enumerate them. A few relics of less interest, and dating from the reign of Elizabeth to the eighteenth century, but belonging principally to the seventeenth, are classed under the head of Later English. The total number of objects of archæological interest, irrespective of animal remains, found in or near the sea-beach of Cheshire during the year 1806, amounts to 238.

The new EXCAVATIONS AT WROXETER (Uriconium), though interrupted for a while by the necessity of employing the men in the labours of harvest, have produced some very interesting results, of which we intend to give a more full account on an early occasion. The new room opened, adjoining to what was named the enameller's shop, and, like it, facing the Roman forum, proves to be another shop, of exactly similar dimensions and character. It is singular that two large workshops, evidently for the manufacture of small ornaments in metal, should stand side by side in such a position; and we may almost suspect chat Uriconium was a great manufacturing town-a Birmingham of Roman Britain. Future researches will, no doubt, throw more light on this question. Among the numerous relics recently discovered, was a pretty intaglio, engraved in a bright red cornelian, and representing two parrots, seated on what appear to be two vessels, with a large vaze between them, into which what bears resemblance to a stream of liquid flows from their mouths. We regret to say that, just as this object was carried to the Museum, some visitors who happened to be there were allowed to take it in their hands to examine, that it quickly disappeared, and that nobody has heard of it since. Fortu. nately, impressions had been taken in wax; but it cannot but be believed that, whoever has it in his possession, will soon see the propriety of returning it to its right place in the Shrewsbury Museum.

We would call attention to a very ingenious and probably correct suggestion made by Mr. Roach Smith, in his Notes in the last number of the “Gentleman's Magazine. Every one at all acquainted with the Roman antiquities of our island, knows how frequently large HOARDS OF ROMAN COINS are found buried in the ground. The Anglo-Saxons had remarked this circumstance, but they imagined that the Romans, when they left the island altogether, nourished the hope of coming back again, and that they buried their treasures, in the idea they would thus be preserved till their return. It is a remarkable circumstance, that nearly all these hoards contain almost the same proportions of the coins of the different emperors; that the most numerous are those of Tetricus, father and son, and that the least numerous are those of Aurelian, with whom they almost all conclude. Mr. Roach Smith compares two hoards recently discovered, one at Netly in Hampshire, the other in Yorkshire, and therefore in widely distant parts of the island. In the former, consisting in all of 1821 coins, there were 749 of Tetricus the father, 255 of Tetricus the son, and one of Aurelian; in the latter, out of a total of 3095 coins, there were 1097 of Tetricus the father, 434 of Tetricus the son, and four of Aurelian. Mr. Roach Smith conjectures, and we are quite of his opinion, that when, at that eventful period in the history of the Roman empire in the west, the legions in Britain and Gaul, who had supported the usurpation of Tetricus, were called into the latter province to oppose the advance of Aurelian, the soldiers of the legions in Britain, before their departure, buried these hoards, and that the owners never returned to reclaim them, being slaughtered probably in the great battle which restored the western provinces to the empire of Rome. A comparison of these hoards is further interesting to us, as it shows us the proportions of the coinage of the different emperors in circulation at the close of the third century.

T. W.

PROGRESS OF INVENTION.

ARTIFICIAL MEERSCHAUM, ETC. — Chemistry has discovered a new and interesting use for potatoes and other vegetables, illustrations of which are now to be seen at the Paris International Exhibition. If potatoes are peeled, macerated for about thirty-six hours in water, to which eight per cent, sulphuric acid has been added, well washed with water, dried in blotting-paper, and then in hot sand for several days, on plates of chalk or plaster of paris, which are changed daily, being compressed at the same time, an excellent imitation of meerchaum, answering well for the carver, or any purpose not requiring a high temperature, will be obtained. Greater hardness, whiteness, and elasticity will be produced if water containing three per cent. of soda, instead of eight per cent. sulphuric acid is used. And if, after the potatoes have been macerated in the solution of soda, they are boiled in a solution containing nineteen per cent. soda, a substance resembling stags horn, and which may be used for knife handles, etc., will be formed. Turnips may be used instead of potatoes in the production of the artificial horn; and if carrots are substituted for the potatoes, a very excellent artificial coral will be obtained.

RAILWAY SAFETY SWITCII.—It is of the utmost importance that the points on railways should be in the proper position. If they are not, a train may run on the wrong line, and thus destructive collisions ensue.

Such has been but too often the cause of serious accidents, and great mischief to both life and property. The pointsman may be neglectful, or over fatigue may cause him to forget his duty. Hitherto there were no effective means of discovering the circumstance until it was too late. A very ingenious and simple application of electricity now renders it extremely easy. The switch is so arranged that, whenever it is not in a proper position, it completes the electric circuit of a galvanic battery, and the current thús set in motion operates on an electro-magnetic apparatus, which keeps an alarm bell ringing where it cannot but draw the attention of responsible persons to the pointsman's neglect, so that the switch may be put in its proper position before any injury is done.

DIANUFACTURE OF STARCH.-An improvement of considerable importance has recently been made in the manufacture of starch. It is founded on the fact that, although the specific gravities of the starch and of the substances associated with it in the grain, etc., from which it is extracted are very nearly, they are not quite the same; and the improvements, which is due to M. L. Maighe, consists in an ingenious application of centrifugal force. Water is added to the crude starch in the proportion of two parts of the former to one of the latter, and the mixture is introduced into a copper drum which is capable of making some hundreds of revolutions per minute. As soon as the proper velocity has been reached, the starch, having a greater specific gravity than the water, and therefore being more affected by centrifugal force, is driven with such violence against the circumference of the drum that it forms a solid mass of great whiteness and purity, being entirely separated from the other substances, which remain suspended in the water.

This method of obtaining pure starch has peculiar advantages: it requires only a few minutes, while the ordinary process takes several weeks; it is more economical, since with it the yield is twenty per cent. greater, and hence starch may be profitably manufactured from other matters besides wheat, which from its nutritious quali. ties should be as far as possible kept for food; and, finally the cellular tissue, gluten, etc., which are very valuable, but by the ordinary modes of manufacture almost entirely go to waste, may be utilized. It is not improbable that a similar application of centrifugal force might be advantageously applied to the separation of other substances differing but little in specific gravity.

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A new BLASTING POWDER.—Vast quantities of explosive material are now used in the operation of blasting; and hence numerous attempts have been made to discover new and better explosive compounds than gunpowder. The efforts which have been made in this direction have not, as the discovery of nitro-glycerine attests, been without success. The dangerous nature of that substance, however greatly limits its utility. Wilhelm and Ernst Fehleisen have formed a compound which is in several respects superior to any of the explosive materials hitherto used. It cleaves, rather than blows into atoms : an important quality, especially when it is employed in the coal mine. It does not ignite spontaneously, nor is it set on fire by friction or percussion. Its combustion gives rise to no opaque, nor suffocating gases, which makes it very valuable in the operations of tunnelling. It has but one disadvantage: weight for weight, it is twice as bulky as gunpowder ; but even this is in a great measure compensated by the fact that it is one-half more powerful. It is formed by thoroughly mixing nine parts by weight saw-dust obtained from a light and non-resinous wood, or wood from which the resin has been extracted, from three to five parts charcoal, and forty-five parts saltpetre, and, if required to be quick, one part ferrocyanide of potassium; the mixture being moistened with one quart of water to every hundred weight. It is granulated by stamping or crushing, and the grains may be polished in the ordinary way; this, however, will merely improve the appearance without increasing the explosive power. This compound has been termed Haloxylin.

The COLOURS OF THE STARS.—The determination of the precise tints of the stars is not only a matter of interest but importance ; and an instrument for this purpose has recently been invented. The object proposed by the inventor was to compare the tint of the star to be examined with that of a solution, the colour of which is known. For this purpose, a platinum wire is rendered incandescent by means of two elements of a Smee's battery; and the rays of the artificial star, thus produced, are made to pass through small phials, filled with solutions of known tints, and attached to a drum which has radial openings, and is capable of revolving, after which, they pass into the objective of a small telescope. The artificial and the real star are compared; the drum being turned until the rays from the incandescent platinum appear of the same tint as those from the star. When the tints are the same, it is known that the proper solution has been used, and the tint of this solution being known, the colour of the star is found.

MAGNETISM AND THE METEORITES.- From the fact that meteorites consist invariably and almost exclusively of nickel and iron, it might, at first, be concluded that the small planetary bodies which are now known to circulate in such numbers in orbits intersected by the orbit of our earth, especially in August and November, consist only of these metals. But the conclusion would not be legitimate, if it be true, as there is reason to believe, that gravitation is not the only force which causes meteorites to be precipitated on our earth. It is remarkable

as

that the constituents of meteorites are iron and nickel, two eminently magnetic metals. And it is not improbable that gravity is aided by magnetism, in attracting these bodies to the earth. Only bodies, therefore, containing iron and nickel reach us, because gravity unassisted by magnetic attraction is unable to draw bodies otherwise constituted out of their orbits.

STEAM APPLIED TO RAILWAY BREAKS.—The safety of a train not unfrequently depends on the power of quickly bringing it to a state of rest. This can be effected only by breaks. The more rapidly, therefore, and powerfully these can be brought into action the more they contribute to the safety of the train. Manual power, to be at all effective, must be slow; and hence, independently of its being very limited in amount, an accident may occur before it has had sufficient time to come properly into play. Steam therefore is now being substituted in America for the muscular power of the breaksman, and with most excellent effect. A steam cylinder of small bore, but of considerable stroke is placed in the locomotive, under the driver's foot board. The steam is turned on or off this cylinder, by means of a handle which projects through the foot board. A chain which acts on all the breaks of the train is attached to the extremity of the piston rod. The pressure is never allowed to become so great

to cause the wheels to slide, that in the cylinder being regulated by a safety valve attached to it. The power which may be given to such a break is practically unlimited. That with which the experiments were tried was capable of exerting a force of three thousand five hundred pounds; and of stopping within a space of seven hundred feet, a train moving at the rate of fifty-six miles an hour.

New PRESERVATIVE COMPOUND.—Many substances have been employed for the preservation of animal matters, and with greater or less success. Most of them are, however, liable to the objection of difficult application or expense. A compound which is cheap and easily applied, and is very effective, especially in the preservation of anatomical specimens, has recently been discovered. It is made by adding to about fourteen parts glycerine, two parts brown sugar, and one part nitre; the addition of the sugar and nitre being discontinued as soon as a slight deposit begins to be formed. Immersion in this fluid for a number of days, dependent on the size of the object to be preserved, effectually preserves organic substances from putrefaction, without, at the same time, altering their appearance. When first lifted out they will indeed, be in the highest degree rigid, but on being placed for a while in a warm dry place they will become as pliant as ever.

New EXPLOSIVE COMPOUND.—Experiments made on the effects produced by nitrate or chlorate of potash on glue have led to the discovery of a new and extremely cheap explosive compound, which may be employed with special advantage in conjunction with ordinary gunpowder. This compound may be obtained by either of two methods. According to one of them, two parts glue are washed with cold water; then heated moderately with a small quantity of nitric acid, evaporated, again mixed with water, and freed from

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