previously deposited to be ascertained. This 100 deg. or 120 deg., is used to feed the boiler. NOTES ON RECENT SCIENTIFIC DIS- 4 New Gas Furnace-An Improved Steam A out of the reach of the water and its destructive influence. Accordingly, a slip 375ft. in length was prepared, with an inclination of 1 in 16, upon which were placed the movable platforms carrying the artificial blocks. These latter being completed, the platforms are drawn down the slip by an endless chain arrangement, set in motion by steam power. So soon as the block has descended to the required depth it is seized by a crane; the platform, relieved of the weight, immediately floats upon the surface of the water, and is easily drawn up again upon the slip. About thirty blocks, with their separate platforms, can be accommodated at the same time upon the slip. As it is frequently an important consideration to be able to build a slip for temporary purposes wherever any work is carried on near rivers and coasts, unprovided with facilities of this nature, we give a description of the one alluded to. Strong square upright piers of masonry are built as the foundations proper; upon the tops of them, which are at different levels to suit the slope, are fixed three longitudinal balks 7 ft. Gin. apart from centre to centre, and with their upper surfaces slightly cambered. The frame or box in which the blocks are manufactured is a strong timber construction, and rests upon the three longitudinal balks, the outer two of which are furnished with little rollers carrying the endless chain mentioned, which is connected also with the barrel of a large winch. It sometimes happens that, notwithstanding the surfaces of the balks are always kept well lubricated, the platforms or cradles stick, and it then becomes necessary to start them from NEW gas furnace for obtaining very high behind, which is accomplished by a lever. temperatures has been invented by M. The chief point to be attended to in putting Perrot. In some respects, we might say it netogether slips of a temporary character is, cessarily resembles the furnaces of Messrs. Grit that the foundation should be as immovable fin and Gore. The peculiarity of M. Perrot's as the nature of the ground will allow, or furnace, however, consists in the fact that, otherwise, the motion of any heavy weight instead of using one large Bunsen's burner, as upon them will cause an unequal settlement in Mr. Griffin's furnace, or a particular arand the transit of the load is sure to be im-rangement to distribute the air and flame, as peded, and every practical man knows the trouble and difficulty experienced in getting a fresh start. Having made the blocks and run them down on their cradles to the required distance, the final and most interesting part of the work is the operation of depositing them in their permanent position. A floating frame, partly of iron and partly of timber, is first constructed, supporting at the four corners an equal number of winches, to which are attached the suspension chains, carrying at their lower extremity the iron rods described at the commencement of the present article. The winches employed have a double purchase, and are worked each by four men. When this floating frame is supplied with all the necessary apparatus and gear, it is hauled, during a high tide, exactly over the block to Although aniline dyes are for the moment be transported to its site. So soon as it is somewhat out of fashion, chemists, doubtless of fairly over it, the four rods are passed through a certain revival, still occupy themselves with the holes bored in the block previously, a the search for new shades of colour and half turn is given to them, a small washer cheaper modes of production. The greatest slipped upon each to make all secure, and advance made of late has been made by the suspension chains hauled taut by the A novelty in steam engines is also described Girard and De Laire, who have found means crabs. The tide continuing to rise, the frame by M. Girard, who has made an engine on the of producing three new and distinct colouring becomes immersed, until, according to the plan described to pump the water from La matters from the residue of the manufacture law of hydraulic equilibrium, a portion of it Villette to the heights of Chaumont. The of rosaniline. It is known that, in making is sunk sufficiently deep to raise the block machine in some respects resembles the rosaniline, only one-fourth of the aniline emfrom its bearings upon the platform. This double-cylinder engine of Woolf. The gene-ployed is converted into that dye. Another separation being effected, the frame, together rator is composed of two vessels, either of with the block, is towed to its destined site, which can furnish separately the steam to the and there made fast by means of buoys and engine, and both heated by the same fire, the guide lines established in connection with second, in fact, by the waste heat. The enthe shore. The foregoing operations recall, gine is double, with two unequal cylinders, on a much smaller scale, these so successfully one working at high and the other at low carried out in the floating of the Britannia pressure, both acting on the same shaft, and tubes to the base of the piers and abutments working separately in case of repairs. The they now occupy with so much utility to the public, and with so much credit and honour to all concerned in placing them there. The block being fixed exactly over its future bed, all that remains is to lower it accurately and safely down through the intervening water. Before commencing this process the tide is allowed to run out until the water is sufficiently low to permit the position of the blocks in Mr. Gore's, the inventor employs a number Sulphate of alumina is now replacing com. mon alum in many manufactures. It is cheaper, and contains relatively a much larger proportion of alumina. It often happens, however, that the material, as sold, contains free sulphuric acid, which is very objection. able, especially in calico printing and paper making. Since the salt has an acid reaction, the free acid cannot be recognised by the ordinary simple test; but Giesérke gives a method simple enough to be employed by any common workman. The test is a decoction of logwood. When sulphate of alumina free from acid is added to the decoction, a very deep reddish-violet colouration is produced; but if only a very small proportion of free sulphuric acid is present, the colour produced is yellowish brown. A standard solution of soda added until the proper reddish-violet colour is seen will show the amount of free acid present. fourth is recovered by distillation; but onehalf has hitherto been lost in the black residuum, for which no, or only limited, applications have been found. The authors named have, however, discovered that this residuum is composed essentially of three distinct bodies, to which they give the names mauvaniline, violaniline, and chrysotoluidine. high-pressure steam passing from the boiler These three bodies they can prepare either to the smaller cylinder works by expansion, from the residues or directly. We give very regulated by a governor having lost heat succinctly their process as revealed in the French here, the steam is reheated by being carried patent. They start with an aniline that boils through a system of tubes in the flues towards at trom183 deg. to 188 deg. Centigrade. This the bottom of the chimney, and now is passed they oxidise with arsenic acid to produce rointo the larger cylinder of the second, which saniline. After heating for four or five hours is a condensing engine. The water from the to 170 deg. Centigrade, they treat the procondenser, which is still at a temperature of duct with boiling water, which dissolves the 3100 deg. or 120 deg., is used to feed tu Experience has proved that, w bination, an increase of from cent. of power is obtained wi consumption of coal. The varie in the first cylinder is regulated sochronal governor with four by M. Girard. That peculiar body, ozone, wie posed to play such an importan ture, has undergone some fare e tions by M. Soret. Our chemi probably remember that a year this chemist arrived at the that the density of ozone was in a half times that of oxygen. Hey molecule of oxygen as composed f 00, and the moleculæ of cate of three atoms 0 0 0, occupying a space as the two. In fact, when ther removed from ozonised oxygen by iodide of potassium, no change in of the gas takes place; but via: oxygen is submitted to heat, and t restored to the condition of art the volume of the gas is increased The density of ozone, therefor, one and a half times that of ordinary: and this M. Soret considered he ha He now publishes a series of conne periments, based on the law of Gases diffuse with a velocity in inverse ratio to the square roots ties. Guided by this law, M. S the rates of diffusion of pure p ozonised oxygen with a miita 1 and oxygen, and also with com and he found that the velocity d of the mixed oxygen and one exactly with the theoretical rat the assumption that the density is one and a half times that ofthe f Sulphate of alumina is now Fiat mon alum in many manufa cheaper, and contains relatively a proportion of alumina. I fe however, that the material, a free sulphuric acid, which is vaga able, especially in calico prin making. Since the salt has an the free acid cannot be regu ordinary simple test; but G method simple enough to be empl common workman. The test of logwood. When sulphate of from acid is added to the decocta deep reddish-violet colɔuration à p 1 but if only a very small propartit !sulphuric acid is present, the co is yellowish brown. A standard an soda added until the proper colour is seen will show the a acid present. salts of rosaniline and chrysotoluidine, leaving spherical shot which was fired from the 300-engineering establishment attached to a large THE following notes of vessels turned out, in The committee deemed it desirable that the front armour-plates should be removed, and on the target being stripped, it was found that the 3in. plates were much less distorted than the 44in. armour-plates on the "Warrior" target, was much less than might have been expected from their thickness. The armour-plates were band, and on order, indicate the present forced back upon the edges of the horizontal condition of work on the Clyde. Messrs. Blackplates in the backing by the blow of the projec- wood and Gordon have launched a screw tiles, were furrowed by the contact in the imme- steamer, which is intended for the Leith and diate seat of the blow, and indented to a con- Baltic trade, and which has been named the siderable distance on each side, but were "Leith." She is the largest steamer ever unbroken, and, except in one or two instances, launched at Port Glasgow, her dimensions being : uncracked; they compared favourably at the Length, 300ft.; breadth, 36ft.; depth of hold back with the 5in. plates which were used in the to main deck, 19ft. The "Leith "is to be engined original construction of the Samuda target. The by her builders. Messrs. W. Denny and Brothers, backing proved much more substantial than the of Dumbarton, have launched the "Sumatra," backing of wood without the interposition of the screw, built for the Peninsular and Oriental iron plates, which seem to prevent the crushing Company, and to be fitted with engines of 500of the wood and the spreading of the fracture to horse power. Although of somewhat greater the contiguous portions of the backing. It would tonnage, the "Sumatra" presents a close resem also probably tend to prevent ignition from the blance to the "Bangalore," recently launched explosion of shell, and evidently affords great by the same builders for the P. and O. Company. support to the armour-plate, as was shown by the The Inman line steamer the "City of London" furrows on the rear of the plates. has recently been lengthened and thoroughly overhauled in Messrs. Tod and Macgregor's dock at Partick. line insoluble in weak acids are formed princi- THE CHALMERS TARGET. The It is understood that Messrs. Robertson and Co. have contracted to build a paddle steamer, 180ft. in length, for a South American firm. The engines will be made by Mr. D. Rowan, Glasgow. The "Royalist," screw, built by Messrs. Blackwood and Gordon for Sir James Brooke, Rajah of Sarawak, has left Port Glasgow for Borneo; she made a very sucSteele and Co.'s graving dock at Greenock, and cessful run to Queenstown. The screw steam has left the Clyde for Davis's Straits. Messrs. Tod and Macgregor are building a cargo vessel for the Inan line. whaler "Lion" has been overhauled in Messrs. power. screw steam yacht for the Earl of Cardigan; They have also launched a T the present moment the Chalmers target she has been named the "Sea-horse," and is to A is attracting considerable attention in be fitted with direct-acting engines of 60-horse France, where some interesting experiments are power. Messrs. M'Nab and Co. have contracted now being made. We briefly noticed these last to build a screw steamer for the Liverpool and week, and hope upon the conclusion of the expebuilt for the North German Lloyds by Messre. Belfast trade. The "Weser," steamer, recently riments to place the detail particulars before our readers. In the meantime it may be interesting Caird and Co., is of the following dimensions:Length of keel and fore-rake, 325ft.; breadth of to note the performances of this target in Eng. land. We, therefore, make the following extracts beam, 40ft.; and depth of hold, 33ft. She is from the reports of the Iron Plate Committee for propelled by engines of 500 horse 1863, referring to the Chalmers system of naval Messrs. Caird and Co. have now in course armour-Mr. Chalmers' target consisted of of construction another steamer of larger wrought-iron hammered armour-plates 3in TRANSPARENCY OF RED-HOT METALS. Duncan and Co., of Port Glasgow, have launched dimensions for the same company. Messrs. R. thick, backed by alternate horizontal layers of timber planking, and iron plates, behind which THE following letter upon the above subject a screw, named the "Grecian," of 850 tons, TH was a second armour plate of 13in. thick, with appears in the Chemical News :-"One of the builders' measurement. The length of this a cushion of timber 3 in. thick between it and contemporaries, though not a strictly scientific steamer is 240ft., her breadth is 28ft., and her the in. plate, forming the skin of the ship. The periodical, of your valuable paper, calls attention depth 17ft. 6in. The engines, which are to be of armour-plates were secured to the skin by 24in. to a highly curious and startling fact observed 100-horse power, are to be supplied by the Finthrough bolts with shallow square threads. The and communicated by the reverend and highly nieston Steamship Works, Glasgow. The paddle eminent savant, Father Secchi, of Rome, concern- steamers "Washington aud "Lafayette," target was fired at with steel and cast-iron pro- ing the transparency of iron while red-hot. The belonging to the French General Transatlantic jectiles from the following guns:-68 pounder fact that iron, steel, and also platinum and Company, and built at Greenock by Messrs. smooth-bore, with cast-iron shot and shell, and 161b. charge; 110-pounder Armstrong, with cast-copper, are transparent while at a bright red Scott and Co., are about to be sent round iron shot and shell, and 12lb. and 141b. charges; tical engineers, but, as regards iron, steel, steamers by Messrs. R. Napier and Sou. heat, has been known long since not only to prac. to Glasgow to be converted into double screw 300-pounder Armstrong, with cast-iron spherical shot and 50lb. charge; and lastly, with a steel The account given of the manner in which the copper, and platinum, to workers in these metals. solid shot of 3011b. from the 300-pounder excellent member of an eminent society found Armstrong with 45lb. charge. The experiment out this property of iron is as follows:-The proved that this system of backing affords great reverend father had ordered a strong iron tube support to the armour-plates, and prevents their to be made. As it was intended for an appa. distortion from buckling. It is also of consider ratus requiring a vacuum, it was essential that able advantage in adding strength and resisting this tube should be perfectly air-tight; and as power to the structure. No other target designed Father Secchi had doubts about its for naval purposes has resisted a similar weight soundness in this respect, in order to set these of shot with so little injury. This report is dated at rest the tube was made red-hot and taken the 26th February, 1864. into a dark place, when Father Secchi clearly The following are extracts from reports and perceived through the iron, which was half a opinions of the committee, Appendix 39-1864:- centimetre thick, a crack inside the tube, and A comparison of Mr. Chalmers' target and the which did not reach to the outer surface. It is original "Warrior" target shows the following rather curious that the fact of the metals above results. The indentations caused by the 68 alluded to, to which I have reason to believe pounder solid shot were in Mr. Chalmers' target that gold may be added, becoming transparent 35, in the "Warrior" 27. But the buckling of at red heat should have escaped the notice of the plate was very much less in Mr. Chalmers' scientific men. It requires, however, a good target than in the "Warrior." No material bright red heat; but the transparency of the damage was done to the skin of either target. A metal is evident thus even in daylight, as I know slowest 18 to 24 miles. In Italy the quickest 24 to comparison is made between the first round of from my own experience while working in an | 30 miles; the slowest 15 to 24 miles. Although aniline dyes are fr somewhat out of fashion, chemis a certain revival, still occupy the the search for new shades of cheaper modes of production advance made of late has be Girard and De Laire, who have of producing three new and disat matters from the residue of the of rosaniline. It is known th rosaniline, only one-fourth of the ployed is converted into that dr fourth is recovered by distil half has hitherto been last 12 residuum, for which no, or 15 applications have been found named have, however, discr residuum is composed distinct bodies, to which they mauraniline, violaniline, and cap These three bodies they ca from the residues or directly. succinctly their process as reveleit patent. They start with an at trom183 deg. to 188 deg. C they oxidise with arsenic sc saniline. After heating for fo deg. Centigrade, some A comparison of a large number of examples has enabled the railways commission to make the following statement:-In England the express trains run generally, including stoppages, about 40 miles per hour; the average of all the examples of the quickest trains (omitting suburban) gives 36 miles per hour; the ordinary trains run generally from 18 miles to 30 miles per hour; the average of all the examples of the slowest trains gives 19 miles In France the express trains run, inper hour. cluding stoppages, 25 miles to 35 miles per hour; the average of the quickest examples is 31 miles; the ordinary trains run from 16 miles to 25 miles per hour; the average of all the examples of the slowest trains is 18 miles per hour. In Belgium the quickest trains run from 29 miles to 35 miles per the quickest 29 miles; the slowest 17 to 21 hour; the slowest 18 to 23 miles. In Prussia miles. In Austria the quickest 20 to 29 miles; the slowest 14 to 21 miles. In Bavaria and along the Rhine the quickest 24 to 32 miles; the SENSITIVE FLAMES. * BY W. F. BARRETT. ROFESSOR TYNDALL, in his lecture at the Flames, has stated my relationship to the latter subject. It is briefly this. In 1865, while preparing the experiments for one of the Christmas lectures at the Royal Institution, I noticed that the higher harmonics of a brass plate (which I was sounding with a violin bow in order to obtain "Chladni's figures") had a remarkable effect on a tall and slender gas-flame that happened to be burning near. At the sound of any shrill note the flame shrank down several inches, at the same time spreading out sideways into a flat flame which gave an increased amount of light from the more perfect combustion of the gas. Having drawn Professor Tyndall's attention to this influence of certain notes on a naked gas-flame, with his consent I followed up the observation by a short investigation, of the results of which he was unaware, with a view to ascertain the cause and exalt the action of this singular phenomenon. I subsequently heard that a somewhat similar but reverse effect to that which I had observed had been noticed in America, and for the first time read the details of these experiments in the lecture to which I have referred. I was then made aware that Professor Leconte had noticed (in 1858) that musical sounds caused the spasmodic jumping of a fish-tail gas-flame, and had made the happy observation that the flame did not jump until the pressure of the gas caused it to be near flaring. Having submitted Professor Leconte's discovery and my own simple observation to a careful examination, Professor Tyndall incorporated the results in his elegant lecture demonstration of January 18 last. As, however, that lecture dwelt almost entirely upon the action of sounds on gas-flames rendered sensitive by increasing the usual gas-pressure-which, with many, introduces a difficulty in the repetition of the experiments I have thought it worth while to publish the following brief record of my experiments, made with gas burnt direct from the main. The experiments for the most part were executed at my own home, during the months of June and July, 1866. The general effect noticed is as follows:-A gas flame burning from the tapering jet B, fig 1, B FIG.I. FIC.3. FIG. 2. B gives the appearance represented in that figure. It is a dull quivering flame, throwing off clouds of unconsumed carbon. When a shrill note is uttered or played, this flame at once shrinks in height and spreads out in width, taking the shape shown in fig. 2. In the first figure the flame has From the Philosophical Magazine. the plate thus sounding close to and parallel with higher notes of the plate were sounded. Holding the flame, a more strained and intense divergence took place; the flame was, in fact, almost split in two, the edges becoming denser and the gence never reached down to the burner. Slowly moving the plate so as to bring different parts in succession opposite the flame, the principal nodal lines could be traced as easily as with sand. The intervals of rest in the vibrating plate allowed the flame to raise itself up, and in its sluggish combustion to stand, as it were, at ease, whilst the ventral segments dragged it down to active burning and apparent attention. As a lecture illustration, this method of showing the higher vibrations of a plate will be found useful where an audience is unable to look down upon the plate to see the arrangement of sand on the In this, as in all other experi. ments, the surprising change in the brillancy of the flame is a most striking part of the phenomenon. nodal lines. a loose and ill-defined shape; in the second it a mental notes of these forks caused the flame to *Nothing is easier than to form such a burner; it is This and the next experiment I made at the Royal In- I observe that Professor Leconte has previously noticed that his fish-tail gas-flame exhibited pulsations in height + For lecture see MECHANICS MAGAZINE for January 25, exactly synchronous with the audible beats of a musical instrument. 1867. Whilst making some of the foregoing experi. the pressure of the gas had an important inments last summer, I was led to observe that fluence upon the divergence of the flame, and remarked that an increased pressure acted like a shrill sound in spreading out the flame, which gave at the same time a roaring noise. Professor Leconte has, however, decidedly the prior claim to this observation, which Professor Tyndall has raised to an explanation of the phenomenon. Professor Tyndall remarks, "The gas issues from its burner with a hiss, and an external sound of this character added to that of a gas-jet already on the point of roaring is equivalent to an augmentation of pressure on the issuing stream of gas." This explanation is, I believe, the only distinct one that has yet been given; and I think the following observations confirm and supplement it. I noticed that if a sensitive flame be gently blown the flame it shrinks and diverges exactly as if it on through a glass tube, while blowing on the were under the influence of sonorous vibration, and it diverges the more strongly the nearer one blows to the root of the flame. The flame also very forcibly diverges when a fiddle-bow is drawn across or a wetted finger drawn down the metal or glass tube which conveys the gas to the burner; if the tube be of india-rubber, giving it the slightest shake causes the flame to diverge, a rapid fluttering of the flame being produced when the tube oscillates. Professor Leconte has compared the movement of the flame to that of a liquid vein under the Professor Tyndall, in his lecture, has shown that by slightly increasing the pressure of the gas the flame is sus eptible of even greater sensitiveness than is shown in this experiment. the plate thus sounding close to and per higher notes of the plate were sonded the flame, a more strained and gence took place; the flame was in split in two, the edges becoming des central part a mere film of flame; b gence never reached down to the bare moving the plate so as to bring differ succession opposite the flame, the princi lines could be traced as easily a The intervals of rest in the vibrat allowed the flame to raise itself sluggish combustion to stand, as it were whilst the ventral segments dragged i active burning and apparent stren lecture illustration, this method of s higher vibrations of a plate will be fa where an audience is unable to look oms the plate to see the arrangement of sand a nodal lines. In this, as in all other ments, the surprising change in the br the flame is a most striking part of the menon. The divergence of the fame is unt de impact of translated puffs of air, biting caused by sonorous vibrations. The easily proved. For instance, standing yards from the flame and bringing forcibly together as if to clap them, b short of doing so, the flame remains ming. the slightest clap, however, at once pr strong divergence. It is astonishing a sound affects the flame, notwithstandig tervention of solid obstacles; pa will illustrate this. Whistling bas effect on the flame, especially so the siteS obtained by blowing into a key. Tar I served the flame, a friend whistling left the room wherein was the fame, ing the door after him, slowly retreated though its action was enfeebled by dis door, the flame still continued to sta in whistle, and was visibly affected even whistle was sounded where it could hav heard, in a closed apartment three saris It certainly is a most wonderful thing sider, how almost infinitely smail is of vibratory motion sufficient to aber a pletely the aspect of a large famed this sensitiveness of such a gas-fam di sounds would lead one to hope that RE put to some use for experimental or purposes. The chirp of a cricket w no doubt, have an energetic action flame. Speaking to the flame i um voice at a distance of 30ft. or 4) A a very marked divergence. It was the letter s had a very strong effect especially with some burners; and it w curious to watch the flame as it mocked any person who happened ing. E MAY 31, 1867. THE MECHANICS' MAGAZINE. influence of sonorous vibrations, and has shown maximum. Since the publication of this paper in the Philosophical Magazine, I have more closely investigated the appearance of the divergent flame in a moving mirror. As already shown, the flame when diverging is in a state of rapid vibration. This vibration is isochronous, and gives 339 freight was two loaded cars, weighing with the THE INSTITUTION OF MECHANICAL Referring to Mr. Ellet's description of crossing One curve pose holding their next annual meeting in Paris on Tuesday, June 4, and following days. The meetings for the reading and discussion of papers will take place in the Lecture Theatre of the Conservatoire Impérial des Arts et Métiers, on Tuesday, Wednesday, and Thursday afternoons; the chair will be taken at two o'clock p m. by the President, John Penn, Esq. The Council have prepared a map of Paris, a sketch of the will be found most useful to intending visitors. Exhibition, and some general information, which The papers to be read are as follow:-"On the Ventilation of Public Buildings," by General Morin, Membre de l'Institut, director of the Conservatoire Impérial des Arts et Métiers ; "On the Flow of Solids, with the Practical Application in Forgings, &c.," by M. Tresca, Engineer Sub-Director of the Conservatoire Impérial des Arts et Métiers. nery for Boring Artesian Wells," by M. Dru, of Paris (Mulot and Dru, artesian well borers); the Construction of the Suez Canal," by M. "Description of the Dredging Machinery used in Borel, of Paris (Borel, Lavalley and Co., contractors for dredging the Suez Canal); "On Floating Docks and other Arrangements for Affording Access to Ships for External Repairs," by Mr. Frederick J. Bramwell, of London; "On lans, of Dowlais Iron Works, Merthyr Tydvil; Mechanical Puddling," by Mr. William Mene"Description of a 30-ton Horizontal Duplex Hammer," by Mr. John Ramsbottom, of Crewe; and "On the Transmission of Power by Water Pressure, and the Application of Hydraulic Apparatus at the Paris and Lyons Railway Station," by Sir William G. Armstrong. "On the Machi THE WHITWORTH RIFLE. rise to the musical note just mentioned. But the are as many as sixteen curves of 604ft. radius recently published, it appears that steel rate of vibration-as evidenced by the number T Whilst making some of the foregoing a ments last summer, I was led to dr the pressure of the gas had an impr fluence upon the divergence of the remarked that an increased pressure shrill sound in spreading out the di gave at the same time a roaring me Leconte has, however, decidedly ther to this observation, which Professor raised to an explanation of the p Professor Tyndall remarks, "The its burner with a hiss, and an ex this character added to that of a gas the point of roaring is equivalent tion of pressure on the issuing stren explanation is, I believe, the only that has yet been given; and I ing observations confirm and supp noticed that if a sensitive flame be on through a glass tube, while bing the flame it shrinks and diverges en were under the influence of sour and it diverges the more strongly 6dd blows to the root of the flame. Î very forcibly diverges when a across or a wetted finger drawe did or glass tube which conveys the gu if the tube be of india-rubber, ! slightest shake causes the fame a rapid flattering of the flame being pas the tube oscillates. 1 t Professor Leconte has compar of the flame to that of a liquid Professor Tyndall, in his lector, Is slightly increasing the pressure of the eptible of even greater sensitivene STEEP GRADIENTS AND SHARP There was completed early in 1863, an incline a reversing station, that is to say, the motion of Y a return relative to army Whitworth rifles barrels for short Whitworths have beenl manufactured by four different firms, at a cost per finished barrel as follows:-Frith and Sons, Sheffield, have made 1,540 barrels, at £1 2s. 2d.; Cornforth, of the same place, 1,391, at £1 2s. 5d.; Messrs. Barger, of Witten, Westphalia, have made 3,678, at £1 4s. 6d.; and Messrs. Whi worth and Co., of Sheffield, have made 1,497, at £3 4s. 4d. A hundred barrels of Messrs. Whitworth and Co.'s make have also been examined and passed at the Enfield small arms manufactory. The above cost includes the wages, the value of the material, the back and front sights, nipple, and breech screw. The reports of officers commanding regiments or battalions to whom the Whitworth rifles were issued, respecting the efficiency of these rifles for the service, are very long, but the following is the gist of the opinions they express:-Since 1857, six different kinds of rifles have been issued for trial-namely, the Brunswick, Miniè, short Enfield, naval, Westley-Richards, and now the Whitworth. The 60th Rifles seem to like the latter the least of all, but their complaints are exceptional; they, however, comprise, and may taken as a sample of, the defects found by other regiments. The rifle is found fault with because of the liability of the locks and nipples to get out of order, the latter especially during rapid firing, through the melting of the platina ring at the base of the touch-hole. The ammunition is complained of as being too delicate and com. plicated in construction for active service. It is too long for the pouches, and the lubricating mixture placed at the base of the bullet is apt to adhere to and harden on the sides of the barrel, and thus causes a difficulty in loading. Ou the other hand, the greater part of the regi ments express themselves as satisfied with the weapon. There have been but few misfires; the figure of merit is satisfactory, the lower trajectory than other rides renders less feit the disadvantage consequent upon ill-judged distances, and the liabilito to fouling is small, while the velocity and power of penetration are such as to commend the Whitworth as น serviceable military weapon. be ENGINE. R. S. DEACON, of the Kennet Ironworks, close contact by set screws passed through the In our engraving fig. 1 represents a top plan MReading, has obtained letters patent for engine shown partly in section, and as it would view of the cylinder of an oscillating steam some improvements in the construction of appear when constructed according to this inoscillating engines, and which are illustrated invention; fig. 2 is an elevation at A; fig. 3 an the above engraving. This invention consists in end elevation; fig. 4 plan; and fig. 5 elevation of adapting a combined steam chest and valve to the cylinders of oscillating steam engines whereby all steam connections with the trunnions of the cylinders are dispensed with. The follow. ing is an example of the means by which the above object may be accomplished:-There is a raised face near each end of the cylinders with a steam port formed in the centre of each. The steam chest is a fixed hollow box with a partition therein, so that one half of the chest communi. cates with the exhaust, and other half with the steam pipe leading from the boiler. The chest is formed with steam and exhaust ports at top and bottom of the faces corresponding with the ports in the raised faces upon the cylinder. One of the trunnions of the cylinder passes through the steam chest, so that as the cylinder oscillates the ports in the faces thereof will be brought opposite to the steam or the exhaust ports in the steam chest, according to the position of the piston in the cylinder. Suppose the piston to be at the bottom of the cylinder the steam port at the top of the cylinder will be opposite to the exhaust port in the steam chest, and vice versa when the piston is at the top of the cylinder. For varying the cutting off of the steam Mr. Deacon employs a loose plate placed between the cylinder and the steam chest, which is worked by an eccentric or other suitable means. The faces of the steam chest and cylinder are kept in pansively. ASSOCIATION OF GAS MANAGERS. T tends to hold its annual general meeting June ex at Nottingham on the 11th, 12th, and 13th of Mr. Thomas Hawksley, president of the Association, will take the chair. Besides a lecture by Dr. Letheby, "On the Utilisation of the Residual Products of Coal Gas," the folcylinder detached. Fig. 6 is an edge view of lowing list of papers and communications will be the improved steam chest; fig. 7 an elevation submitted to the meeting:-"On the Practical thereof; fig. 8 a section through the line A B at Working of the Liquor System of Purification," fig. 7; fig. 9 is an elevation; fig. 10 an edge view, being a statement of results in continuation of fig. 11 a top plan view of an expansion plate the paper of last year on "An Improved Method which we shall presently particularly describe. of Purifying Coal Gas," by Mr. George T. LiveA is the cylinder; B B' trunnions, which may be sey, South Metropolitan Gasworks, London; formed solid; C portion of framing to carry the "On the Purification of Gas from Ammonia, and cylinder; DD lugs and bosses formed on C; EE the Utilisation of the Product," by Mr. George set screws passing through screwed holes in the Anderson, London; "Notes on the Manufacture bosses of D; these screws are employed to keep of Sulphate of Ammonia," by Mr. W. Esson, the faces of the steam chest G and expansion Gasworks, Cheltenham; "On the Application plate H in close contact with the faces of the of Liquid Hydrocarbons, as a Substitute for Canports on the cylinder, as seen at fig. 5, where a anel, in the Manufacture of Gas for high illumi mark the steam ports. The construction of the nating power," by Mr. E. Goddard, Gasworks, steam chest Gwill be best understood by refer- Ipswich; "Some Remarks on the Explosive ring to figs. 6, 7, 8, where bb mark the induction, Properties of Firedamp and Coal Gas, with and c c the eduction ports; I the supply pipe, Particulars of Experiments made in Lighting and K the exhaust; the dotted lines d d mark Portions of the Oaks Colliery with Pit Gas," by the partition in the steam chest. The construc- Mr. J. Hutchinson, Gasworks, Barnsley; "On tion of the expansion plate is shown at figs. 9, 10, Leakage from Gas Mains," by Mr. E. S. Cathels, 11, where e e mark openings or ports; ff faces Gasworks, Crystal Palace District; "On the of the plate H, which together with the faces on Valves of Gas Purifiers," by Mr. W. J. Warner, the steam chest and cylinder should be made Gasworks, South Shields. true and steam-tight. The part g of the plate H is for the purpose of connecting a rod thereto to be worked by an eccentric for cutting off the steam at any desired part of the stroke, as usually practised in steam engines working ex The Federal Council has resolved to invite tenders for the second series of the loan to meet the expense of supplying breech-loaders to the Swiss army. The amount required is 6,000,000f., and will bear 4 per cent, interest. |