sist of more than one series, each of which must be found either wholly, or in part, to discover where the series is of the least value decimally. I have not had time to investigate the rules given by G. C. L., which may be correct, though the first one, upon which the others depend, has an inconsistency in its expression; for if 999, ad infinitum, is to be divided by the given number, there cannot be a last remainder : he probably means that the division is to be made until the figures recur; if so, it is fortunate for him that the answer to my question, which he has chosen to illustrate his rule, happened to be 15 43 to the re else the division MORDAN AND Co.'s NEW PATENT PEN. Sir, It is a great pity that patent speculators, before patenting a thing, do not give themselves the trouble to ascertain whether a similar production to it has been, in any shape whatever, previously before the public. The want of this very necessary precaution exhibits itself in the instance of the three-nibbed metallic pen, advertised in different journals, and exhibited (per engraved card) in various stationers' windows, as a recent patent of Messrs. Mordan and Co. At p. 31 of a pamphlet on metallic pens, by J. Carstairs,* will be found the description of a metal pen, the invention of a Mr. James Gowland, chronometer. * Simpkin, Marshall, and Co. 1835. maker, 11, Leathersellers' Buildings, London Wall, answering precisely to the subject of the present comment. The hardship of individuals losing their inventions, through an incapability of ascertaining what had been before invented and privately made use of, has been altogether removed by the alterations in the law of patents; the public, however, have a just right to benefit by the oversight of patentees where the opportunity exists of information. It is a matter of surprise that gentlemen so long in the field of invention, and bona fide manufacturers into the bargain, as Messrs. Mordan and Co., should have put themselves to the expense of attempting to secure what appears to be nearly, if not quite, a year old. Sir, your obedient servant, SCRUTATOR (pro bono publico). HANCOCK'S STEAM-CARRIAGES. Mr. Hancock still continues to run his steam-carriages on the Paddington road with uninterrupted success. No accidents have happened, nor any derangement of the machinery, unless the breaking of a chain pulley may be so called, which was immediately replaced by another. The "Infant," which Mr. H. yesterday (Friday) brought from Stratford, for the purpose of working on the Paddington-road, is the first steam-carriage that ever ran for hire, which it did on the same road about six years ago, and a fortnight before Sir Charles Dance commenced running on the Cheltenham-road with Mr. Gurney's drag. The " Infant" seems in excellent condition, and apparently not any the worse for the occasional working it has had since its birth. The rate of travelling during this week has been about the same as last; averaging one hour and ten minutes from the City to Paddington and back, a distance of nine miles. Of this time upwards of one-fourth is consumed in stoppages for coke, water, and passengers. From Monday morning, to Thursday 12 o'clock, sixteen single trips to Paddington were performed, and forty-six to Islington. The number of passengers carried was 711. We understand the carriages will continue to run daily, in the morning from 9 to 12, and in the afternoon from 3 to 6 o'clock, 112 NOTES AND NOTICES. NOTES AND NOTICES. Preservation of Animal Substances.-A pamphlet published at Florence gives an account of a strange discovery by Geralamo Legato, the accuracy of which is attested by the principal professors in that city. It appears that Legato, while traversing the deserts of Africa in 1820, for the purpose of perfecting a map, discovered in one of the hollows which a whirlwind had ploughed up, a completely charred human body, the flesh and bones of which were in good preservation. It struck him that the process of charring could only be effected by the scorching sand, and that if the heat of the sand had in this instance effected the complete disiccation and carbonization of animal substances, it might be possible to effect something similar by artificial means. On his return to Italy, he commenced his experiments, and at length succeeded in imparting to the limbs and bodies of animals solidity, and indestructible durability. By this, whole bodies, as well as individual parts, acquire a thoroughly firm consistence, which is more decided according as the respective parts are harder or softer. The skins, muscles, nerves, veins, fat, blood, all undergo this change without its being necessary to remove the intestines, which assume the same consistence. At the same time the colour, form, and character, in general, remain changed; no smell is perceptible, and both joints and limbs remain flexible and moveable as when alive. When bodies have acquired this consistency, neither damp air, moths, nor water can effect them. The weight is but slightly diminished. Not a hair is lost; on the contrary, they are rooted more firmly than ever. Birds and fishes lose neither skins, scales, nor colours, and in like manner insects and worms remain perfect in every respect. Legato's cabinet contains many specimens of this novel and singular discovery. One of the most re. markable is a table composed of 214 pieces joined together. The observer would take them for so many different kinds of stone, and yet they are nothing more than portions of the human members.Scotsman. un- Colossus Redivivus.-An Englishman has lately erected on the banks of the river Theiss, in Hungary, a mill in the form of a colossal man. The head is the dwelling-house, the eyes serving for windows, and the nose for a double chimney. The machinery is placed in the body, and set in motion by a stream of water from a canal in the form of an immense bottle, which the monster is emptying into his mouth.-Times. How is the water raised into the bottle?-Q. New Percussion Gun.-The Wirtemburg papers Occupy themselves much about experiments made with a percussion gun, of the invention of Duke Henry, by means of which an able soldier can fire eight or ten shots in a minute. Wonders of Mechanism.-The Hague Journal states, that a Dutch artilleryman, named Vander Boll, having 1 st both his arms below the elbow, by an explosion, the sculptor, J. F. Freit, of Flushing, has contrived and executed for him two artificial fore arins and hands, with which he can feed himself, put on his clothes, perform all other ordinary offices, and even write. (?) The poor man was also deprived of one of his eyes, but for this we suppose no substitute can be found!- Guernsey Star. Sampson Twigg and Co., a firm of three labouring men, obtained permission to work in a mine at Botstone, in this county, the property of Messrs. Gaunt and Challinor, of Leek, and to take the minerals, subject to a certain tribute to the proprietors, for six months to come. The mine is at the bottom of a stupendous mountain. The men began at the bottom of the hill, and after consider able labour were able to strike through some coverings of flint, when they discovered a vein of ore, almost pure lead, and in three days have not raised less than three tons, worth 201, a-ton. It is expected, without exaggeration, that for six months to come they will gain 100l. a-week by their own manual labour, exclusive of the tribute payable to the proprietors; but fears are entertained that their good fortune may cause the death of some of them from over exertion, as they are not to have any assistance. Botstone is within half a mile of the famed Ecton mine, from which the Duke of De vonshire amassed so large a fortune; and what is very singular, these three men have been working at the first-named mine near one year, earning not more than 12s. each a week, and have frequently blasted within a yard of the place where the treasure has been discovered. The face of the vein is not six yards from the surface.-Stafford Paper. Mr. Thomas Sheriff, Westbarns, East Lothian, has invented a plough, for which he has been awarded a premium of five guineas by the East Lothian Society. The property of this implement is to cultivate the subsoil, in opposition to the system of trenching, which was lately introduced into East Lothian, and the tendency of which was to turn down the rich vegetable mould, and raise up the subsoil, in many, nay, in most cases, always the inferior. Its construction is simple, and every common plough can be converted into a subsoil plough at pleasure, and at a trifling expense. It is only calculated to operate successfully on a subsoil which does not afford much resistance; but a plough has been invented in Stirlingshire, which, with a proper application of strength, will cultivate the most stubborn clay subsoil that exists.Farmers' Magazine. Communications received from A SubscriberMr. R. Roberts-Mr. Lunt. "An Old Subscriber" is informed, that we are always willing to publish the particulars of useful inventions without payment. His order on town for cash has been destroyed. Errata. In a few impressions of our last Number, p. 95, col. 2, line 8 from bottom, for " 11,' read "9,"-and line 6 from bottom, for " 11," read "12." The Supplement to Vol. XXIV., containing Title, Contents, Index, &c., and embellished with a Portrait of Mr. Walter Hancock, C. E., is now published, price 6d. Also the Volume complete in boards, price 9s. 6d. 114 REPORT OF EXPERIMENTS ON THE EXPLOSIONS OF STEAM-BOILERS. REPORT OF EXPERIMENTS MADE BY THE The second part of the inquiry relates to the action of fusible plates when in place on the boiler; it supposes proper alloys, fusing at required temperatures, to be composed, and then studies the causes, modifying the action of them when placed on the boiler. In the first apparatus for the use of these plates the attempt was made to introduce them within the boiler, but the difficulty of replacing a plate which had fused by another plate, led to the abandonment of this apparatus. The opening made in the boiler, when the plate was withdrawn, was so great that the contents of the boiler were violently discharged through it before the operation of replacing the plate could be effected. This observation has a bearing upon the plans for making large openings in boilers of full size to avoid explosions. The apparatus finally used was a slidingplate, moving in a groove upon the upper side of the boiler, as shown in figs. 1 and 3, where represents the slide moved by the lever r; in the middle of the slide was an aperture slightly conical, for receiving the fusible plate, this aperture was eight-tenths of an inch in diameter. By means of the lever, the plate could be brought over an opening in the top of the boiler, or the solid part of the slide might be made to cover the same opening. The fusible plate was covered by a disk of brass, the edge of which projected over the plate, and rested upon the slide. There were six holes drilled through this plate, each being about nineteen hundredths of an inch in diameter. To retain the slide in its place, when pressed from below, and to retain the fusible plate when in a similar situation, the forked stem L, pressed in the former position by one leg upon the slide s, in the other by the other leg upon the disk covering the fusible plate; the upper end of the stem entered a cavity in an adjusting-screw t, passing through the gallows u; by this means allowance could be conveniently made for expan sion. The lever for moving the slide rested, when the aperture in this latter for receiving the fusible plate coincided with the opening in the boiler, against an upright, projecting from the top of the boiler, and serving as a stop. By the use of this apparatus, the plates were applied very readily, were removed when fused, and the opening into the boiler closed with so much dispatch, as to prevent the foaming within from taking ef fect. The disk which covered the fusible plates prevented in part the loss of heat from the upper surface. The plates which were first cast were intended for low pressures, as most convenient for experiment, they were fifteen hundredths of an inch in thickness. The observations made upon the manner in which they acted when in place upon the boiler, led to the question of the effect of varying the thickness upon their use. When a plate of sufficient thickness to prevent its giving way to pressure, verges towards its point of fusion, the top part, which is in contact with the metal disk, melts, and flows over the holes in the disk; sometimes it accumulates until the liquid rolls off the plate. The temperature rising, a small pellet of the more perfectly fused parts is thrown out by the steam, the flow of which is instantly checked ; this is repeated frequently, until a breach through the plate is made, and the uninterrupted flow of steam takes place. If the plate be removed at once, a very small hole appears, which would gradually have been widened by the action of the escaping steam, probably before the entire fusion of the plate. The under surface of the plate appears oxidised, and the fusion to have taken place at the top: the plate has contracted in its dimensions, and the periphery of the upper surface has lost its circular figure, which is tolerably well preserved by the lower surface. To give some idea of the extent to which a plate such as just supposed may lose its substance before giving way, two measurements are subjoined. Before fusion the diameter of the upper surface of the plates was eighty-four hundredths of an inch; the lower diameter eighty-two hundredths of an inch: the thickness of the plates, fifteen hundredths. After the plate had given way, the diameter of the hexagonal figure into which both the surfaces had passed, was about seventy-nine hundredths for the first, seventy-four hundredths for the second; the diameter of the lower surface, which was still nearly circular, was, for the first, seventy-six hundredths; for the second, sixty-nine hundredths; the thickness of the first was about twelve-hundredths, of the second, one-tenth of an inch; the thickness not being uniform in all parts. The first plate had lost, therefore, nearly three-tenths, and the second half of its substance, without allowing the passage of steam. The observed oxidation of the lower side of the plate led to the supposition that it might retard the fusion of the plate, but no confirmation of this view was given by comparative experiments with plates of which the lower surface was brightened, and of others in which the same surface was highly oxidated, the thickness in each case being the same. In the course of the experiments on the effect of oxidation, the plates were much re duced in thickness by filing away the under surface, and the fusion of the thinner plates took place ut points so much lower than those at which the thicker plates of the same alloy gave way, so as to require an examination of the cause. Before proceeding with further detail, it may be well to state the general method of experimenting upon the plates. The stationary point of an alloy having been determined, and remarks made as to its point of fusion, plates were cast from it; and one of these being placed in the opening in the slide of the apparatus already described, was covered with the pierced disk, and the slide moved so as to bring the plate over the opening in the boiler. The steam was now raised, the temperature being noted from time to time, until the plate gave way; steam was then let off to keep the temperature from rising; the plate, which had just fused, removed, and one of an alloy, fusing at a higher temperature, substi tuted. The steam was again retained, and allowed to rise in temperature, the new plate pushed to its place, and the operation renewed. This course was continued until the alloy, fusing at the highest point of those prepared, had been used, or until the limit of the elasticity of steam, which could be produced in the actual condition of the boiler and state of the fire, was attained; steam was then let off, water thrown into the boiler, and a new series commenced. The tables which will be given required many days of trial and of close attention. To try the effect of thickness on the fusion of the plates, three different thicknesses were cast of each of the alloys used; the first, or thickest, was fifteen-hundredths of an inch thick; the second, eight-hundredths; and the third, four-hundredths. There were five dif ferent alloys of tin, lead, and bismuth, composed; the stationary points of which, and the points at which they gave way in the boiler, appear below. The plates of Experiments 1, 2, and 3, were exposed to pressures tending to render them of less than one atmosphere; 1 and 3, the two extremes of thickness, show a great uniformity in the point at which they give way, and render it probable that some flaw, in casting the plate number two, caused its fusion at a lower point than that of either of the others; we see, too, that at these low pressures the fusing point in the boiler coineided very nearly with the point at which the alloy was a soft solid in the crucible. In this case the thinnest plates, when properly cast, were probably thick enough to withstand the small pressure to which they were exposed, and therefore did not give way at lower temperatures than the thickest, each attaining the temperature at which they were soft solids. The next series, Nos. 4, 5, and 6, with a less fusible alloy, show, first, that the thin nest plate was too feeble to resist the pressure of steam. and gave way before the metal lost its solidity; second, that the plate, eighthundredths of an inch, was probably defective, as it gave way at a lower temperature than the thinner plates of No. 4. No 6 presents a curious fact; the point of yielding of the |