used. THE VELOCITY OF STEAM. ing of the Irish constabulary. Lieutenant | himself. Great was the outcry of the natives McMurray dates from Fort Wardsworth, when the works of the Egyptian Railway Tauids are matters of the first importance New York Harbour, April 4, 1867, and began to invade the sacred precincts of the reports upon the practical use of the Spencer Nile with the foundations of a fine bridge. to the practical engineer, and, in fact, to all repeater as a breech-loader. We may observe A greased cartridge was the cause of, or pre- who are interested in promoting the economic that we ourselves have used the Spencer in text for, a murderous rebellion among the use of steam. These subjects have of late enthis way before the arm was mechanically native troops in India; whilst alarm and con- gaged the attention of Mr. R. D. Napier, who altered, although it was merely done as an ex-sternation were attendant upon the introduc- has studied them both in their theoretical and The results of his periment to prove that the gun could be so tion of gas into Singapore. But science has their practical bearings. Of course this required careful, if not triumphed; and although the traditions of studies and experiments have been embodied delicate manipulation, although Lieutenant certain worshippers have been rudely invaded, in a very interesting pamphlet, which he has M'Murray was able to make a practical the Egyptian crosses the broad bosom of his recently placed before the scientific world. arrangement to suit the purpose of actual war. god in a railway carriage with no more com- Mr. Napier discloses some very surprising It appears that during the summer and fall of punction than we do the Thames; whilst the effects of the expansion of gases on their velo1865, Lieutenant MacMurray was out with the Hindoo gladly displaces his cocoa-nut oil by cities, from greater to less pressures, through expedition on the northern plains and used the subtle and unseen spirit of gas, even in his tubes and orifices, as obtained by actual exthe Spencer rifle himself, and had it in the very temple. And it is to be hoped that each periment. He also gives the reasoning by hands of mountain men and Indian guides, has had his perceptions quickened, and that the which he was enabled, in a great measure, to and by attaching a thong to the small of the shriek of the locomotive and the blaze of the anticipate those experimental results; and stock and to the lever, allowing just a suffi- gas burner have cleared the ears and eyes of it is remarkable how these agreed with his cient amount of play to start the shell out of many an one from the meaningless sounds formulae, considering that the latter were obthe barrel without opening the magazine, it and mists that ages of isolation and darkness tained without any assistance whatever from The mission the former, but were arrived at entirely by could be used more rapidly than the "Sharp" had gathered around them. rifle with a reserve of seven in the magazine of each is to humanise and enlighten; in the reasoning on the probable effects of expanIt sion. Two of the conclusions at which Mr. for Indians. One day two mountain men and name of science, then, let the work go on. nine soldiers (eleven in all) fought their way is somewhat curious, and to us far from hu- Napier has arrived are surprising, if not steadily on foot through an encircling force of miliating, to contemplate the inroads of science startling; first, he states that the greatest not less than 12,00 to 15,00 Sioux and upon classic territory, and to notice how rate at which steam will flow from a boiler Cheyeune Indians. The moral effect of the quietly she places her heel upon some popular through an orifice into a vacuum is only half, constant fire from so few arms, with the accu- delusion, or upsets some theory which the or rather less than half, of that given in all rate fire at long range, kept the Indians sanctity of ages had hallowed into an indis-published tables on the subject. Considering beyond arrow range (60 to 125 yards) and putable principle. The matter-of-fact half- the vast amount of research that has taken the men rejoined the command without a yearly reports to shareholders drop in occa-place upon all questions relating to steam, wounded man. sionally, and show how John Company is revo- this proposition certainly appears incredible. Two men started from camp to hunt; they lutionising and reclaiming; obliterating poet-But what will be said of the next? Here the were pursued by twenty, some say, twenty-ical associations by docks, harbours, railways, author states that steam at a pressure of two or five Indians, who overtook one of them and telegraphs, manufactories and gasworks. And more atmospheres will rush from a boiler, killed him; the other tumbled from his mule this last word "gasworks" just reminds us through an orifice or short tube, into the air rate as it will into a into a little gulch and commenced firing; he that it was upon that subject we had a few at exactly the same killed one Indian and two horses and words to say. vacuum, or into any pressure less than that wounded three Indians, who with the others of an atmosphere; and, generally, that a gas galloped off, when he pursued his way to the of any given pressure will rush from one vessel command again unmolested. Frequently into another containing gas of half that prescharges would be made on small detachments, sure at the same rate as if there were a perand the Indians were invariably repulsed fect vacuum in the recipient vessel, or any when the men had the Spencer. The Burnintermediate pressure between a vacuum and side and other carbines are said to have half the pressure in the cistern; both presThe author proved useless, the army pistol (Colt's and sures being taken from zero. Remington's) being better than either. The frankly tells us that he does not expect this bow and arrow in the hands of an Indian is to be credited, although it is a fact neverthesuperior for their use to any rifle, as at 60 less, and one which he has taken a great deal to 80 yards they can throw them with such of trouble to prove beyond the shadow of a rapidity as to keep from five to seven in the air reasonable doubt. at one time, seldom failing to hit a man at that distance, even though their horses are at full gallop. In fact, they seem to shoot better when in motion on horseback than when on foot and standing still. the East. And On Our readers are doubtless aware that Singapore and Bombay have been lighted with gas for the past two years. Taking into consideration the mixed population of Singapore, and the prejudice of the natives upon the introduction of any new undertaking from the fear that it will interfere with their religious tenets, the progress made by the gas company is highly satisfactory. The fact that Malays, Klings, Chinese, Arminians, Parsees, Javanese, Bengalese, Jews, and other classes of natives are consumers of gas argues well for the success of the undertaking, and indicate progressThese results were first deduced theoretisive enlightenment. As a matter of fact we may mention that at the close of last year cally by Mr. Napier, and were afterwards there were in Singapore 341 public lamps, proved, as regards tubes, by two perfectly 539 houses, 4,409 private lamps, and 21 cook- dissimilar kinds of experiments. Each kind ing stoves lighted with gas. The practical consisted of two divisions, differing widely They carry from forty to seventy arrows, point to which we would direct attention is from each other, and, as regards orifices, by a and when firing take about seven or eight at the character of the coal best suited for gas sufficient number of experiments to show a time from the quiver and hold them with making in we gather that the same law applied to them as to tubes. the bow with the left hand, pulling the notch the particulars report of Mr. These experiments are all carefully detailed of the arrow and the string with the right. E. J. Wells, the Singapore Gas Company's by Mr. Napier, and knowing that he was venresident manager, which has The Spencer is the only arm which, in any recently turing on debateable ground, he has been sent to us. The experience and very careful to make his arguments and derespect, compares with the bow at the latter been range-equally accurate, equally rapid-but the careful observation of the past six months monstrations lucid and indisputable. former cannot so well be used on horseback, working have led Mr. Wells to the conclusion perusal of the pamphlet itself it will be found but its long range compensates for that. The that Australian coal is the most suitable, pro- that the author has fully succeeded in estaIndians got several rifles from men they had vided the proper description be procured. His blishing the two main conclusions at which he killed and were seen to load them by the reasons for this opinion are that in the first has arrived. Wide discrepancies have hitherto muzzle with buck shot, and after unsuccessful place they have enabled him to dispense with existed between the theoretical and expeefforts to fire them threw them away, although the use of cannel coal, and yet to maintain the rimental laws, especially between those relatthere were yet several cartridges in the maga-illuminating power of fourteen candles. The ing to gases, which many have in vain tried zine of which they knew nothing. Lieutenant Australian coal is very free from sulphur, to reconcile. It is peculiarly satisfactory, M'Murray concludes his report by observing much more so than the English coal. Then then, to find, at least for once, a theoretical that all troops for the plains should be armed it may be stored in large quantities in safety; law in the latter and more difficult branch of with Spencer rifles as they are not only a some put in store in June last year did not the question, corroborated by experiments to superior arm but the most economical in show any signs of deterioration or of heating a remarkable degree of exactness. We must every respect after first cost. We may observe at the date of Mr. Well's report (Feb. 4, 1867); at once admit the superior force of reasoning that a paper is to be read on the subject of consequently a large stock can be laid in with that predicts extraordinary results which are breech-loading firearms, by Captain O'Hea, safety. In Singapore they can be laid down afterwards verified by experiments, to that of before the Society of Arts next Wednesday at a lower rate than that at which coal can be reasoning which is simply employed to explain evening, when the merits of all the most re- procured from England, especially if a year's the facts themselves after their existence has cent breech-loaders will doubtless be dis- supply is taken at the season when ships can been ascertained. cussed the Spencer rifle amongst others. pass through Torres Straits. These facts, however unimportant they seemin themselves, may nevertheless have a material interest to other enterprises in this direction, whilst the main bearing of the whole is, that the arts and # "On the Velocity of Steam and other Gases, and energy, are gradually overspreading the whole the True Principles of the Discharge of Fluids." By R. D. NAPIER. London E. and F. N. Spon, 48, Charing Crose. GAS IN SINGAPORE. HE practical applications of science have some parts of the world; they have made shipwreck of many a good pagan's creed-or of world. All Mr. Napier's experiments were tried with steam only, but as they corroborate the truth of reasoning which is applicable to all gases, what is proved of one may be predicated of all, allowance, of course, sets firmly in from half to three-quarters of an We may mention here a curious fact recently being made for their densities. The general NOTES ON RECENT SCIENTIFIC DIS- New Uses for Mica-Process for Bleaching for the protection of our country, our vast com. merce, and our colonies. Having referred to the various vessels which he had proposed since 1855, to those which were now built or building on his principles, he proceeded first to show the advantages of the turret syatem, and then to the demands of the increasing power of ordnance. describe the vessel which he proposed to meet broadsides, he said that nineteen ships built on As to the economy of turret ships compared with the latter principle would cost for their construction £1,572,782 more than turret ships; besides, the consumption of fuel in the former would be greater, and 3,124 more men would be required to man them. It might be said that it would be impolitic to reduce the number of men in the navy; but now, when men were becoming scarcer and more expensive, it appeared to him to be of the greatest importance that we should be able to man more ships with fewer men. One of the greatest advantages of his turret system top of the turret. The gunner was protected by was, that in firing guns aim could be taken on the a circular disc. He had a clear range of vision from the aperture, and could search the whole horizon for his enemy. This will be made clear by an examination of Captain Coles's most recent improvements in the turret system, as illustrated in the MECHANICS' MAGAZINE for December 7, 1866. In a broadside ship, said the Lecturer, aim had to be taken from the port. The gunner's range of vision was confined to that area, and in general he had to depend upon the information received from the upper deck as to the The materials for making a chemical experi- whereabouts of the enemy. He had to stand ment which affords some entertainment are about 15ft. from the port, which was a great sold in Germany with directions for obtaining disadvantage in the taking of sight, and in pro"a winter landscape in a bottle. as These portion USCHER, of Nurnberg, has lately sug- materials consist of a colourless liquid in a convenience was increased, and his having the gun was elevated that inP gested the use of mica for various decorative purposes. For one such application, bottle, which is really a solution of nitrate of to move about from right to left to search an object caused unsteadiness and the thin plates are first purified by treatment lead, one part to three of water; and a box of for with strong sulphuric acid, and then silvered fragments of sal-ammoniac of about the size delay. The turret-port at the instant of firing by the ordinary process adopted with looking of small beans. About 2in. of a bottle or glass could be turned in the direction of the enemy's glass. The mica thus acquires a beautiful are to be filled with the solution, and then fire and closed in seven seconds. Breech-loaders silver lustre, and it may easily be cut into any pieces of the sal-ammoniac are to be dropped could prevent any guns being loaded in the ports shapes to be used for inlaying work. The in to cover the bottom. The double decom- of a broadside. Shot and shell could be poured into the ports of a broadside during all the time flexibility of the mica will of course allow of position which ensues with the two ingredients the guns were being run out and Åred, whilst a its being applied to round surfaces. When a causes the deposition of a white crust, upon turret port would be only partially exposed for, sheet of mica is heated to full redness for a which is seen projections which seem to be at the most, thirty seconds. time in a clay muffle, it loses most of its flexi- miniature representations of trees, bushes, bility, and is changed considerably in appear-grasses, and rocks all covered with snow. ance. Under reflected light it has a dead Readers who think of amusing themselves by silver white look, but viewed by transmitted repeating this experiment must remember that light it is seen covered with grey spots. nitrate of lead is a poisonous salt. This latter appearance is lost when two or three pieces are super-posed, and the transparency is lost. The mica after heating is also a beautiful material for inlaying work. It should be cut into the shapes required before it is heated. Another very pretty effect is obtained by scattering small fragments of mica on freshly poured sheets of gelatine, and varnishing it with a dark-coloured solution of gelatine. Finely ground mica on coloured gelatine also shows very pretty effects; and the very finely ground material mixed with a solution of gum arabic may be used, Puscher says, for silver ink. simple process for bleaching glue, and give it readers. The next ad. Suppose, continued Captain Coles, that guns were fired from the ports of the "Bellerophon," the exposure at the ports would be seven times greater than in the case of a turret ship, and all practical men would admit, that the difference The means of distinguishing between the would be enough to decide the fate of any action. presence of free alkali and alkaline reacting In firing heavy ordnance, a turret ship would salts in soaps may be useful to some of our have great superiority over a broadside, on acCalomel may be employed for the count of the greater precision of firing in the purpose. A solution of soap containing free former, which would be obtained by the greater facility of taking sight of objects. alkali when added to calomel causes the vantage of the turret system was, that a steadier separation of the black sub-oxide of mercury. gun platform was ensured by a lower freeboard, It is more convenient, however, to use a solu- and as monster guns had come into fashion; tion of a mercurial salt, and one of corrosive that advantage was of the utmost importance. This Another advantage was, that whereas in a heavy sublimate will answer in most cases. will give a precipitate of the yellow oxide of sea the guns of a broadside might be buried in mercury if free alkali is present. It is said, water, no such casualty would take place in the Turret ships were suphowever, that this test does not answer in the case of a turret ship. case of the resin soap used by paper-makers, and posed to be most uncomfortable; but, in fact, Puscher, therefore, recommends, the use of they had good spacious decks, and his ex We read in Dingler's Journal of a very neutral sub-nitrate of mercury. A cold solu- perience of all classes of vessels assured him our readers for what it is worth, without com- tion of resin soap must be employed, since the mitting ourselves to the perfect success of the resin acids themselves will with heat decomoperation. Ordinary glue-in tolerably thin pose the mercurial salt. sheets, we presume-is to be soaked in moderately strong acetic acid for a couple of days. At the end of this time it is to be drained, placed on a sieve, and well washed with cold water. Dried on a warm plate after this, it is said to give sheets almost as white as, but somewhat more brittle than, bone gelatine. If a purer glue is used the colour of the bleached product is much nearer to that of bone gelatine. If this process should answer it is certainly simple and cheap, as the author states. TURRET VERSUS BROADSIDE SHIPS. requires no introduction to our readers, in The author before quoted, Puscher, of Nurnberg, also gives a cement for fastening Service Institution on Wednesday evening last, brasswork upon glass, particularly adapted for petroleum lamps. It is essentially a resin Captain Fishbourne, R.N., occupying the chair. soap, made by boiling three parts of resin In opening his lecture Captain Coles observed with one part of caustic soda and five parts of that the title might appear out of date, since the water. This is mixed with half its weight of plaster of Paris. Such a cement, it is said, has great adhesive power, is not permeable to petroleum oils, is a bad conductor of heat, and turret system was now admitted to be the right fired with ease. that turret ships would afford better accommoda- Mr. Reed, the Constructor of the Navy, criticised some of the statements of Captain Coles. While he admitted that that gentleman's invention had a great many merits, he contended that Captain Coles's enthusiasm had claimed for it more merit than it possessed. 30.159 2,750 Aneroid or cor rected barometer. Height in feet. barometer Aneroid or cor rected 10,250 21.283 21 050 in. ft. in. ft. 50 100 150 in. 31.000 2,000 28-807 4,000 26-769 6,000 24.875 30.943 2,050 28.754 4,050 26.720 6,050 24.829 30*886 2,100 28.701 4,100 26.671 6,100 24.784 28.649 4,150 in. ft. ft. in. 8,000 23.115 ft. 10,000 8,050 23.072 10.050 26.622 6,150 24.738 200 30.773 2,200 6,200 24.693 6,250 4,350 26.427 6,350 This table is intended more particularly for the graduation of aneroids with a circle of measures in feet concentric with the ordinary circle of barometric height measured in inches. The circle of feet is to be read off, at the upper and lower stations, by the index; and the rule for measuring the height will be:-Subtract the reading at the lower station from the reading at the upper station; the difference is the height in feet. The table supposes the mean temperature of the atmosphere to be 50 deg. Fah. or 10 deg. Centigrade. For other temperatures the following correction must be applied:-Add together the temperatures at the upper and lower station. If this sum, in degrees of Fah., is greater than 100 deg., increase the height by 1-1000th part for every degree of the excess above 100 deg.; if the sum is less than 100 deg., diminish the height by 1.1000 part for every degree of the defect from 100 deg. Or, if the sum in Centigrade degrees is greater than 20°, increase the height by 1-550th part for every degree of the excess above 20°; if the sum is less than 20o, diminish the height by 1.550th part for every degree of the defect from 20°. 22.200 11,100 20.630 9,600 has observed during his stay, in reference to the 3rd. The Council think it will be undesirable 4th. A considerable sum will be required satis. factorily to accomplish the important object undertaken by the society, and, in order to raise these funds, the Council have determined to appeal to the members of the society, who must be interested in the successful results of this movement, in the belief that they will not hesi tate to join in a subscription for the furtherance of the undertaking; and they propose at the same time to communicate with the various chambers of commerce, inviting their counsel and support. The Council have decided to commence the subscription by a vote of one hundred VISIT OF ARTISANS TO THE PARIS guineas from the funds of the society. were made by the French Government to facili- premise that the two vessels "Pereire" and and the "St. Laurent" have equalled, and sometimes surpassed, the most rapid runs of the best English steamers. The tables drawn up by the Post Office authorities show that in 11 voyages from Brest to New York and back again, made by the "Ville de Paris," and the "Pereire" between March, 1866, and February, 1867, in an interval of about 12 months, comprising both the summer and winter seasons, the average speed was 12.80 knots, instead of the 11.50 knots required by the terms of the contract. This speed of 12.80 knots has not been equalled even in England; it exceeds by two-tenths of a knot the average runs of the celebrated "Scotia," as stated in official documents. One of the quickest passages on record since the commencement of steam navigation between Europe and New York (after allowing for differences in distance) was made by the "Ville de Paris" between July 21 and 30, 1866, the average speed of that steamer having been 13:60 knots in a run of 3,000 nautical miles, from port to port. The "St. Laurent," built in France, and fitted with a screw apparatus made at Creusot, has had her share of success in this race across the ocean, having taken her place in the line at the beginning of winter only, the three voyages she had made up to the present time have naturally encountered the obstacles peculiar to the season of the year least favourable for navigation. Nevertheless, her average speed has been 11'65 knots; one of her passages was effected at 12:10 knots; and in the last she ran 350 nautical miles in 24 hours for four con. secutive days. These results speak highly in favour of the seagoing qualities of the vessels, and are most honourable to the captains, engineers and all persons concerned in working them. Till now, continues the report, rapid voyages have been the exclusive appanage of our mari. time rivals but at present our French line disputes the palm, and has placed itself in the fore. most rank along with the foreign lines. The patriotic good wishes which have accompanied our undertaking, and the subventions from the Government, which have encouraged it, have thus met with their due satisfaction and reward This But a second very important fact is also made evident by comparing the passages made with paddle-wheel steamers and with the new screw vessels. It consists in the great economy attending the use of the screw steamers which have attained the speed above mentioned. The use of the screw procures for vessels of equal tonnage a saving of about 25 per cent. in fuel, with an increase of 20 per cent. in speed. advantage has been proved in a most decisive manner by the experiment in the "St. Laurent," which was at first intended to have paddlewheels, but in course of building was changed into a screw vessel. It is therefore thought that further applications of the screw ought to be resolutely carried into practice, and the directors have decided on ordering two new screw apparatuses, which will be adapted to the "Washington" and "Lafayette," both steamers remarkable for their excellent nautical qualities and comfortable arrangements as passenger vessels, but too slow for present requirements. The organs of propulsion will alone be changed; the boilers will remain as they are. The system adopted is the double screw, which recent successful trials in England and in the French Imperial Navy prove to possess the advantage of being more easily and more economically adapted than the single screw to vessels already built, at the same time that, by the establishment of two apparatuses of moderate size, instead of very large dimensions, the safe navigation of the vessels will be more completely guaranteed, and the chances of damage or breaking will be avoided. THE CONSTRUCTION OF CHIMNEYS. object of a chimney is to conduct the proTHE ducts of combustion from a fire inside of a house and discharge them into the atmosphere outside. In performing this function it also secures a supply of fresh air to the fire to promote and support the combustion of the fuel. The principle upon which the draught of a chimney is secured and regulated is based on the difference in the specific gravity of the hot air and smoke arising from the fire, and the cold air of the atmosphere. The heated products of combustion, being lighter than the outside air, ascend by their expansive force, and at the same time the colder air descends and flows into the fire to supply the place of the ascending current. It is thus that an out ward current is maintained from a fire, otherwise the smoke and carbonic acid gas would remain in the apartment in which the fire is maintained. The ruling feature of a chimney is to control the expansive current of warm air and smoke, so that its force will be maintained to overcome the pressure of the atmosphere outside and thus maintain an outflowing current. Chimneys are deservedly held to be worthy of high rank among the great blessings of modern civilisation. It is now very well ascertained that such contrivances were unknown to the ancients. The Romans performed their cooking and heating with chafing dishes. There are no chimneys in the houses of Herculaneum and Pompeii, and but few if any chimneys are to be found in the present day on the houses in the warmer districts of Italy. In the thirteenth century chimneys were unknown in England; each family made their fire in a hole in the middle of the floor, which was covered when the inmates retired to bed. It is supposed, though not clearly established, that chimneys were first used in the hilly and colder portions of Savoy and Piedmont, and from thence the improvement was communicated to France, Germany, and England. Chimneys are still unknown among savage races of men. In cold weather they make their fires on the floors of their huts, and the only exit for the smoke is a hole in the roof. Such rude dwellings are usually filled with smoke, which is the cause of frequent inflammation of the eyes, and among barbarous white tribes it colours their skin a rich amber hue, rivalling that of a smoked ham. Several of the rude races of northern Europe have skin as yellow as those of the natives of Southern Africa, all caused by peat smoke. When well scrubbed with soap and water and permitted to reside for some months among civilised people, who have chimneys in their houses, these races become as fair as any of the Anglo-Saxon Celtic family. There is considerable practical science involved in the construction of chimneys. It is well known that many of them smoke, and the plague of a smoky chimney is put in the same category with a scolding wife." Among the first who treated the subject of chimneys in a philosophic manner, was that wisest and most practical of American philosophers, Franklin, who published a treatise on the subject in 1785. This essay was followed by one on the same subject by Count Rumford. These two authors have laid down the principles upon which all chimneys should be built, and the accompanying figures illustrate how the draught may be controlled (as described by an old correspondent) in chimneys which have open fires below on andirons and grates. Chimneys are frequently built in log houses on the plan of fig 1. The fire being built upon the hearth, it has abundance of room to enter the chimney at the flue F, but the hole at the top being small, compared with the flue F, there is no room for the warm air and smoke to get out of the way of the cold air rushing in below, and it will be continually puffing out into the room. On the other hand, if the plan be reversed, as in fig. 2, and the chimney increases in size upward from the flue to the top, the draught will be excessive, and the greater part of the heat will go up the chimney, as in an air furnace. A mediuni between these two plans at fig. 3 will create a regular and not excessive draught. In fig. 3, the flue is (as it should be) the smallest place in the chimney. In ascending from TENACITY OF STEEL RAILS. TELEGRAPHY IN SWITZERLAND. HE Swiss system of telegraphs, like that of State, exclusive of certain wires employed in the service of the railways. The Swiss system now includes 2,130 miles of line, and 3,717 miles of wire. It has 388 instruments, and 252 offices were at the end of the year 1865 open for the receipt and transmission of telegrams, besides 28 so-called offices of deposit. It is found that nearly 14 miles of telegraphic line exist in Switzerland to every 100 square miles of country, and that there is one telegraphic office for every 10,000 persons. A most important feature in this system is the arrangement between postal and telegraphic authorities, by which money orders may be sent by telegraph instead of post. A uniform charge of a franc is made for every inland Swiss telegram, each addition thereto of ten words or under costing an extra quarter of a franc. A free delivery is made within threefourths of a mile of the receiving office. If beyond that distance, the message may be sent post-free or by special messenger, at a charge of half a franc for a mile and a half. The telegra. phic system, as thus conducted, has been found to work as well in Switzerland as in Belgium, and, indeed, the former country shows a larger proportion of telegrams to letters than the latter. land during the year 1854 was 109,600, and in The number of inland messages sent in Switzer rail is now to be seen still in use, and in good which produced a sum of 381,378f. In the former 1865 a total of more than 364,000 was obtained, order, which has outlasted 25 iron rails successively placed next to it on the same line. year the proportion of telegrams to letters was Judging by this example, the steel rails are at 1 to 125, and in the latter year but 1 to 69. It least twenty-five times as durable as iron ones. is fairly probable that this great increase of Steel rails are very tough; as some experiments telegrams at the expense of letters is due to the made within the last few days at the works of natural conformation of the country, which Messrs. John Brown and Co., and Messrs. renders all postal arrangements necessarily Cammell and Co., of Sheffield, conclusively il. slower than those in Belgium, and so increase lustrate. These experiments were made chiefly the advantages of telegraphic communication. for the satisfaction of the Hon. W. J. MacAlpine, much connected with railways in America, who ON NAPHTHA AND ILLUMINATING OIL formerly engineer of the State of New York, and contemplates the more extended introduction of steel rails into that country. The result was to FROM HEAVY CALIFORNIA show the great toughness and powers of endur(MALTHA).* ance of the steel rails. In one of the experiments BY B. SILLIMAN. of a ton weight was sail of 68lbs, to the yard, supported to fall upon a 8 ft. apart in the clear, from a height of 20 ft. feet, and the only effect was to bend the rail. The rail was then turned upside down and the blow was repeated, when the rail was bent straight, but without any cracking being visible. Finally, the rail was exposed to the test of a ton ram falling through 30 ft., when the rail was very much bent and twisted, but not a crack was visible. By the mode of manufacture now adop. ted perfect uniformity in the composition of every rail is ensured. T the Chalk Farm station of the Loudon and THE PRUSSIAN NAVY. HE following details are given in the Journal TAR HAVING lately bimen of surface oil," so called, from Santa Barbara county, in California, I present the following experimental results, in the hope that they may not be without interest, as an addition to our knowledge of one extreme of that class of hydrocarbons which occur in nature in the fluid form, and of every density, from those which are but little lighter than water down to the light est naphtha found in a natural state. It is proper to state that the chemical examination of this sample had chiefly a technical object, to prove whether or not illuminating oil of good quality could be obtained from the distillation of so dense a body. The experiments were conducted on quantities of from five to ten gallons each. The crude oil was very dark, almost black, transmitting yellow brown light in thin films. At ordinary temperatures (60 deg. had an opportunity to ex The de bait anlly representing the Fab.) it is a thick, viscid liquid, resembling 66 " "French commerce," observes the journal quoted above, "would not have much to dread from a navy which hardly reaches the tenth part of that of France." Oil having a density of 890 to 0.900... 69-82 20-18 100-00 In one of these trials the product was divided Oil, of density 29 deg. Baumé at 52 17.5 32.5 100-0 The coke is very large in quantity, strong, and * American Journal of Science. is a good fuel, resembling gas-house coke. The odour of ammonia is given off towards the close of the distillation. which in the larger way of operating commer- No paraffin could be detected by refrigerat It is well-known to distillers of petroleum that by the process called "cracking," heavy oils unfit for illumination are broken up into bodies of less density, from light naphtha to the heavier illuminating and lubricating oils. This process is simply the application of a carefully regulated heat producing a slow distillation. By this treatment the molecules apparently rearrange themselves into groups of different density, which by a subsequent distillation are divided into fractions (or "heaps" as Mr. Warren calls them) of tolerably constant boiling points. The first distillate, having a density of about 890 at The light oils obtained in this series of experi60 deg. Fah., treated in this manner, yielded a ments correspond respectively to 12.96, 14:56, product having a density of about 85 at 60 and 18 96 per centum of the crude oil. The total deg., or only 1 deg. Baumé lower than before commercial products are about 60 per cent. of distillation. After treatment with sulphuric acid the crude body, which likewise yields sufficient and soda and redistilling from soda, it had a coke to supply the fuel required in the distilladensity of 880 at 60 deg. Fah. Upon redistill- tions. In the large way, by returning the ing, 100 measures of this last distillate yielded-lightest oils to the heavier portions in the sucLight oil having a density of about '834 cessive distillations and employing Mr. Young's at 60 deg. Fah. method by pressure, it is probable the product of light or illuminating oils may be raised in these very heavy natural products to 30 per cent. It is evident from these experiments that heavy hydrocarbon oils containing no naphtha are convertible into oils of the naphtha series under the action of heat by molecular transformations, the excess of carbon being left behind as coke; each successive distillation eliminating a new but always a diminished portion of carbon. 21.58 Heavy oil having a density of about 880 at 66 deg. Fah 37.41 Heavy oil having a density of about 916 at 64 deg. Fah.... 34.53 Coke, &c., to 100.00 In another experiment undertaken with a view "cracking," &c., treating and redistilling with soda, the products were as follows, stated in percentages of the whole quantity operated on, the several steps being as before. Naphtha*, specific gravity about '760 at 60 deg. Fah. ......... 11.33 Oil,t specific gravity about 836 at 60 deg. Fah. 66.22 The illuminating oil from both these experiments, after treatment with sulphuric acid and soda in the usual manner, acquired an agreeable odour, a light straw-yellow colour, and burned as well in a lamp as good commercial oil. With a view to test the effect of heas aided by pressure in breaking up the heavy hydrocarbons-3 method of treating heavy hydrocarbon oils patented in 1866 by Mr. James Young, of Glasgow a portion of the first distillate from the crude oil was subjected during distillation to a pressure of 101b. to 15lb. to the square inch, in an apparatus adapted to the purpose, the distillate thus obtained being about the same density as in the first-named experiment, 890 at 60 deg. Fah. From this distillate were obtained, after the ordinary treatment with sulphuric acid and soda, the following products:Light oil, specific gravity 825 at 60 deg. Fah....... Heavy oil, specific gravity *885 at 60 deg. Fab. Heavy oil, specific gravity 918 AT ROYAL INSTITUTION. T the annual meeting of the Royal Institution of Great Britain, held on Wednesday last, Sir Henry Holland, Bart. M.D., D.C.L., F.R.S., President, in the chair, the annual report of the Committee of Visitors for the year 1866 was read and adopted. The books and pamphlets presented in 1866 amounted to 130 volumes, making with those purchased by the managers, a total of 407 volumes added to the library in the year. Thirty-eight new members were elected, and sixty-three lectures and twenty evening discourses were delivered during the year 1866. Thanks were voted to the president, treasurer, and secretary, to the committees of managers and visitors, and to Professor Faraday, and the other professors, for their services to the institution during the past year, The following gentlemen were unanimously elected as officers for the ensuing year:-President, Sir Henry HolJand, Bart. M.D., D.C.L., F.R.S; Treasurer, William Spottiswoode, Esq. M.A., F.R.S.; Seeretary, Henry Bence Jones, M.A., M.D., F.R.S; besides these gentlemen, fifteen managers and the same number of visitors were elected, NEW COLLEGE OF SCIENCE IN TH HE arrangements of the Lords of the Council on Education and the Lords of the Treasury respecting an intended new College of Science in Dublin, provide for the conversion of what has been known as the Museum of Irish Industry into such college. According to the Observer, it will have ten professorships, seven of which The illuminating oil from the last experiment already exist. The professors of applied matheflashed at 80 deg. Fah. and lighted on the sur-matics, and mechanism, and of descriptive geoface at 85 deg. Fab., showing the presence of metry, machinery, and surveying, will have naphtha or some very light body, the quantity of £400 per annum salary, rising to £500. These which cannot be very considerable. The light are new chairs. The professor of applied cheoil could with care be taken off in practice with mistry will have £300 per annum, and will have out materially diminishing the yield an illuminat IRIDIUM IN CANADA, Mexists along with the other materials with MEVES, of Madoc, states that iridium which gold has been found in the Richardson mine. The presence of iridium, says the Keystone News, is not mentioned in the reports of Dr. Hunt and Mr. Michel; but as Mr. Meves has obtained his specimens quite recently, they may have been taken from different parts of the vein or "pocket," as this deposit has been called. Iridium is one of the rare metals, and is of extreme hardness. It was found in Californian gold, and its presence in the gold coined at the United States mint caused the destruction of several valuable dies, and from this led to its detection and removal. The same substance is found in the gold of the Chaudière, as also plati. num, and an alloy of osmium and iridium, named iridosmine. The latter is very hard and durable, and is put to a practical use in pointing gold pens and in jewelling. Platinum, it need scarcely be remarked, is a most valuable metal, and if found in the gold region here, as is quite likely, would constitute of itself a valuable discovery. We mention this to encourage explorers to have their eyes open to other things besides gold. Such a tract of country might also be expected to supply precious stones, as chalcedony, ame. thysts, and other varieties of coloured quartz, jaspers, and even diamonds. MONMOUTHSHIRE STEAM COALS. A a BOUT three years ago, when the celebrated trials took place as to the relative merits of Welsh and North country-coals, certain regulaid down by the Admiralty lations were authorities which practically excluded Monmouthshire steam coal proprietors from coma natural peting for navy contracts; and, as result, the price of the coal in the open market was also affected. It is well known that coal not on the Government list is always put down as a relatively inferior article, and hence it is not surprising that the colliery proprietors of Monmouthshire at once took steps to obtain reversal of the regulations referred to, and which in reality amounted to a virtual denial of the right of Monmouthshire steam coals to be on the Government list. A memorial was got up in reference to the matter, which stated that the steam ccals of Monmouthshire were known as bituminous, and for economic value and evaporative power were fully equal to North-country coals. In June and July, 1863, trials were made on board her Majesty's ship "Fearless," the results shown being that while the consumption of Monmouthshire coal in the production of the same indicated horse power was in one case 40 per cent. and in another 20 per cent less than that of the North country coals, the former produced smoke in a medium volume of light colour, and the North country coal emitted large volumes of black smoke. This memorial was signed by the leading colliery proprietors of the country, and a reply has just been received from the Lords of the Admiralty, stating that the restrictions will henceforth be removed, and instructions to that effect have been given to the proper officers. The decision arrived at has given great satisfac tion, and the result will be that the Monmouthshire and North-country coals will in future be placed on the same footing as regards navy contracts. to instruct the royal exhibitioners free of charge. Ting relates to combing machinery n ing oil. It would be rash to conclude that there Other professors will teach in such subjects as *This naphtha caught fire from a match at an atmospheric temperature of 56 deg. Fah. Fab. MACHINERY FOR COMBING WOOL. HE invention illustrated in the engrav. which circular rotating plates or discs are em. ployed in substitution for the old "dabbing" brushes, for the purpose of pressing the wool or other fibre into the pins or teeth of two rings or circular combs to which the fibre is fed. The present improvements have just been patented by Mr. Clinton Edgecumbe Brooman, of 166, Fleet-street, and are the substance of a communi. cation from M. Amédee Pronvost, of Roubaix, France. They consist in combining with the circular discs an intermediate circular disc, in front of the other discs and between those discs which work between the teeth or pins of the outer ring or comb and those discs which work between the teeth or pins of the inner ring o circular comb. The intermediate disc is placed in the angle at the tangential point of the two rings or circular combs. This intermediate disc is for the purpose of keeping the wool or other |