the composition of so many rocks, was one of na. ture's chief agents of purification. Here the author referred to a series of experiments he had made, showing that the commonly received opinion, that light and air alone effected the purification of water, was erroneous. For example, he had put coloured bog water into shallow glass pans, in which it was fully exposed to both these agencies for several weeks-evaporation being compensated by distilled water-but without any change being apparent in its colour. This result, so contrary to what might have been expected à priori, led him to refer the natural process to the agency of some other body which probably exercised a catalytic action on the atmospheric oxygen, and thereby induced this gas to combine with the noxious impurities existing in the water. Nor was he mistaken in this surmise, as the rasults so amply related in the paper, together with the experi-| ments, exhibited to the section, sufficiently attest. A very striking one was made with some bog water, much darker in colour than ordinary porter, which had been procured from the soakings of an Aberdeenshire peat bed. This water was deprived of colour almost instantaneously by mere contact with the oxide. To appreciate this result it is to be remembered that no known agency has been able to effect a similar one before. Since soft water has become so much an object for manufacturing purposes, to effect the decolouration of that of bogs had remained a problen unsolved by chemists. Not only was it now evident that this water could be deprived of all trace of colour, but it was rendered bright, clear, and perfectly free from taste. Several who partook of it pronounced it to be equal in these respects to spring water. Above all, the means by which the charge was effected were so exceedingly simple. For example, the coloured water was poured into a glass vessel containing a layer of about five inches of equal parts of coarse sand and a hard ferruginous substance, perfectly magnetic, on which the water issued forth with great rapidity, perfectly colourless. The action of the oxide, however, was far from being confined to the decolouration of bog water; that experiment had only been brought forward because it could be strikingly exhibited to a public assembly. On the contrary, it equally affected every impurity to which water was subjectedeven that of the London sewers had been rendered harmless, and void of all odour and taste by the same means. Besides which, it had resulted from the experiments of Professors Brande and Clark, that soft water treated by the magnetic oxide had no action on lead. Perhaps the most extraordinary circumstance was, that the magnetic filtering medium itself suffered no deterioration after any period of operation. Its province was confined to forcing the oxygen resident in the water into combination with the colouring matter, and thus converting it into carbonic acid, which gas, it need hardly be said, conferred freshness and salubrity on all waters in which it was found. In this result the occult action of catalysis was, for the first time in the history of science, brought at will into useful every-day operation in explanation of this extraordinary action, the author now entered at some length on the received notions of what was really to be understood by the term "catalysis." He thought it might be satisfactorily shown that the substances inducing this action did so in virtue of their power to alter the molecular arrangement of the bodies they acted upon-as a magnet alters the arrangement of iron filings, even at a distance. He believed he was in a position to show, how ever, that the phenomenon was strictly identical with electro-polarisation. he had to relate was, that the oxygen when in this For example, a still stronger proof was cited, Mr. Spencer now gave an account of a new compound magnetic body which he had succeeded in making to better enable him to carry out the purification of water on a large scale. Though the magnetic oxide he had first obtained from the white carbonate of iron was very effective, yet it had a tendency to be reduced to powder by attrition. He became apprehensive therefore it might ultimately interfere with the rapidity of his filtering operations. This led him to seek some mode of procuring a harder and less friable body. After ture of ozone. There was another mode of testing the matter, however, which he named, and which, if successful with the magnetic oxide, might carry more conviction to his mind. Mr. Spencer stated that he had not considered the mode named by the President as being so good a test of the presence of ozone as the one he had brought before the section. At the following meeting of the section, however, this experiment was successfully performed by Mr. Spencer, in the presence of the President, thus affording an additional proof that ozone is only polarised oxygen, and that nature is not confined to one mode for its production. been obliged to omit several equally interesting Copious as this abstract appears, yet we have topics embraced in the original paper. COAL-BURNING LOCOMOTIVES. By DANIEL KINNEAR CLARK.“ belong to this system of smoke prevention. The These desirable qualifications the writer believes whole apparatus is external to the fire-box, and therefore not exposed to heat; and it is controlled in the most perfect manner by a single stop-cock. Air is admitted above the fuel by one or more rows of tubes inserted through the walls of the fire-box, and jets of steam are projected through the air-tubes from nozzles th inch diameter, in small steam pipes, placed outside the fire-box, to increase the quantity and force of the air admitted above the fuel in order to consume the smoke. The jets of steam are used principally when the engine is standing, with the aid of a light draught from a ring-jet in the chimney, to carry off the products of combustion, and they may be shut off when not required. The supply of air through the tube may also be regulated by dampers. The grate-bars are placed close together, with. narrow air spaces, and the ash pan and damper are lightly fitted. The level of the fuel should at all times be below the air-tubes. a the engines of the Great North of Scotland RailThis system is working with entire success on way, at Aberdeen. It is also successfully at work daily (amongst other lines) on several of the engines of the North London Railway, where, as nuisance are rigidly enforced. It requires a less Metropolitan line, the regulations against smoke weight of coal than the engines formerly required than the whole difference in the price of the two of coke for the same duty; and thus saves more fuels. various experiments he had been successful beyond his anticipations. By very simple means he had formed a magnetic body from the hitherto refractory Cumberland hematite. The new substance consists of iron, oxygen, and carbon-an equivalent of each-its atomic number is therefore 42. Specimens of the new body were exhibited to the section. It appeared very hard, and when polished had a black metallic lustre. It was said to be as incorrodible as gold or platinum, and is highly magnetic. Its purifying powers were stated to be The locomotive engine has been variously cut very great. It can be manufactured very cheaply. up and mangled in order to suit the views of deMr. Spencer, as its discoverer, had named it pro-signers for the combustion of coal without smoke. In the plan before the meeting, the original type In the experiment he had exhibited, there The President (Dr. Lyon Playfair), at the close of engine promulgated by Mr. Stephenson, and at could, he believed, exist no doubt that the mag- of the paper, was sure the section would feel much this day universally adopted and unsurpassed, is netic oxide of the filter had the power of attract indebted to Mr. Spencer for the valuable nature preserved intact; and the locomotive is thus rening oxygen to its surface, and when there this gas of the practical results he had laid before them.dered a complete and perfect machine, and ennecessarily became polarised. Whilst in that Though much struck with the ozone-forming tirely meets the great railway necessity of the state, and only whilst in that state, it combined experiment in support of the theory, yet he, the day-the perfect combustion of coal in railway with the organic colouring matter to form a new President, hardly felt himself at liberty to give engines. substance. But the most startling circumstance | his adhesion fully regarding this view of the na tocarbide of iron. British Association, 1859. Literature. Our Engines of War, and How we Got to Make As a rapid superficial sketch of the progress made eight small pages of matter in very large type, and it is hardly fair, we think, to the reading public to label such a brochure with the broad and sounding title, "Our Engines of War, and How we Got to Make Them," and to charge six or seven shillings (as is done, if we remember rightly) for it. Many of our engines of war are not mentioned at all in the book, and others are passed over very lightly indeed. It is the publishers, however, we presume, rather than the gallant author, who are responsible for the price and title, and it is as a warning to them that we express dissatisfaction on these points. In other respects they have turned the work out of hand very satisfactorily, the type, wood cuts, &c., being of the best kind. It is due to the author to say that he has made his work very interesting, and has displayed great intelligence in dealing with the various subjects that he has considered. Nor can we refrain from congratulating the public upon the excellent temper and wisdom displayed in the work. There is no jealousy of inventors, no distrust of non-professional men to be found in it; but on the contrary a sound spirit of progress, and a hearty love of improvement manifested throughout. When we remember that the author holds a high military office-that of superintendent of our small arms department-we cannot but hail such evidences of enlightenment with pleasure. Nor is Captain Jervis alone in this respect. From a report which appears in another page it will be seen that Colonel Dixon, who has charge of the works at Enfield, has just been evincing a similar spirit in connection with the Association of Foremen Engineers. We gladly accept such facts as proofs that the old and bad feeling of military exclusiveness, which has cost us so much, is declining, and as omens of its speedy and complete extinction. The Theory of Compound Interest and Annuities, with to the fishery in the early part of 1859, and with has looked into the volume, thinks highly of it. LIST OF NEW BOOKS. Blenkarn's British Timber Trees, 5s. 31s. 6d. Edition, 2s. 6d. M. Ewen's Culture of the Peach and Nectarine, 3s. 6d. Turner's Domestic Architecture in England, Vol. III., 30s. THE PROGRESS OF STEAM NAVIGATION AT HULL. Greenland, and afterwards to the Davis Straits. In the commencement of this year several ordinary iron screw steamers were despatched to Greenland, viz., the Corkscrew, Gertrude, Emmeline, and Labuan, the latter only of this class, which is the property of Messrs. Bailey and Leetham, had any success; but in consequenc of in a tolerable way; the others were much her great strength and peculiar form, succeeded damaged, and, as I have already remarked, returned in bad condition. The Labuan is 581 tons burthen and 40-horse power. steamships of the port of Hull refers to alterations The next point of interest connected with the made in some of the vessels. The Emerald Isle, a paddle timber-built ship of 1835, the property of Messrs. Gee and Co., originally 135% long, lengthened 35 ft., with a gain of 14 in. draught of water, and an increased capacity for 100 tons dead weight. The Sultana, iron screw steamship of 1855, the property of the same house, originally 150 ft. long, lengthened 30 ft. with a gain of 10 in. draught of water, and an increased capacity of about 100 tons. It is interesting to observe that in both cases we have no diminution of speed through the water, and that both vessels are improved as sea-boats. Daily experience teaches the advantage gained, in almost every point of view, by ships of great comparative length. The iron steamship Lion, of Hull, formerly a paddle-boat 219 ft. long, but now converted into a screw steamer by her owners, Messrs. Brownlow, Lumsden, and Co., under the direction of Mr. AnderBy JAMES OLDHAM, Esq., Hull, M.I.C.E.* son, their engineer, exhibits the great advantage FOR generations past Hull has been noted for gained by the alteration. Her register tonnage its Greenland and Davis Straits fishery, and for is 690, and the total tonnage 1,014. She was formany years this has constituted the chief feature of merly fitted with steeple engines of 350-horse the port. Within the last two or three years power, and had four boilers, two before and two steam has been put into successful requisition to abaft the engines; but these were subtituted for aid the dauntless and hardy mariner in the direct action engines of 150-horse power, and two pursuit of this hazardous calling, and now we of her old boilers replaced, and by this alteration have several screw steam-ships employed; and a clear length of hold in midships of 23 ft. is although some of them are fitted with compa- gained. She required before the conversion 650 ratively small power, they have proved to be tons of coal for a Petersburg voyage, and conpossessed of great advantage in the service, and sumed 30 cwt. to 40 cwt. per hour; but now 350 in some instances satisfactorily to the owners. tons for the voyage, and a consumption of 20 cwt. We have had two descriptions of steam vessels per hour. By the change of machinery about 130 employed in the fishery; the first, the old wooden tons of dead weight is removed from the ship, and sailing ships, which had been engaged in the she is now able to carry 400 tons more cargo. service for some years, but which were afterwards Her speed is also improved considerably; before fitted with screw machinery and auxiliary steam the alteration, when drawing on an average 14 ft., power. The second, iron built ordinary screw the rate was six knots and a-half, but since the steam-vessels; but which proved, I believe, al- change, when drawing even more water, they can most a total failure. The material of which they steam eight knots. Thus throughout a saving were built, and the want of strength for such a almost in all the departments of the ship, and purpose, proving them altogether unfit to contend other advantages, have been effected in this imwith the severity of the climate and rough en-portant change. During the last two years many fine steamships have been built in Hull, and becoming total wrecks, while others returned others are in process of building for English and bruised and rent, and were with difficulty kept from foreign service by Messrs Brownlow, Lumsden, sinking. A question here arises how far iron and Co.; Messrs. C. and W. Earie, and Messrs. Marships are calculated to bear the severe frosts of tin, Samuelson, and Co. The last-named firm are high latitudes, and whether wooden-built vessels, making rapid progress in the building of two with all their defects, are not the best adapted large paddle steamships for the Atlantic Royal for encountering such a climate? The screw Mail Steam Navigation Company of the following steam-ship which was first sent from Hull, or any dimensions, power, &c. :other place, to the fishery as an experiment, was the Diana, timber built, 355 tons and 40 horsepower, high pressure, the property of Messrs. Brown, Atkinson, and Co., of Hull. This vessel had been some time engaged in the fishery as a sailing ship; but her spirited owners, thinking an important advantage could be gained, determined upon the adoption of steam power, and at once had the Diana fitted for the spring of 1857 by Messrs. C. and M. Earle, who put in the engines, and made the screw to lift out in case of need. The experiment fully answering their expectations, Messrs. Brown, Atkinson, and Co., bought the Chase, a fine American built ship of immense strength, and of 558 tons. She was fitted by Messrs. Martin, Samuelson, and Co., with con The Journal of the Royal Agricultural Society of attention of our readers. The Drawing Room Portrait Gallery of Eminent put a handsome book on his drawing-room table densing engines of 80-horse power, and despatched British Association, 1839, Length between the perpendiculars Feet.. 360 40 30 2,860 800 Tonnage, builder's measure... fitted fore and aft for passengers. Speed through Since the meeting of the British Association, at Dublin, considerable advance has been made in London and other ports in the application of superheated steam, and, I believe, with great suc cess and satisfaction in the results; Hull, however, before taking a decided step in this important discovery is anxious to see and adopt the best mede of the application of the principle, being assured that in every onward movement it is better "to make no more than good speed." Some attention has been paid to the consumption of smoke in the furnaces of our steam-vessels, and with a con:siderable amount of success. I may here mention the mode of Mr. Ralph Peacock, of New Holland, Hull, for which he has taken out a patent. It consists of a double furnace-door (two views of which are shown in the annexed engraving), the Chamber or space between the inner and outer surfaces being five to six inches in width. The inner plate is perforated very full of small holes, and in the outer plate a revolving ventilator is inserted, which is on the principle of that invented by Dr. Hale, to supply close places with fresh air. The apparatus is in use on board the Helen Macgregor, one of Messrs. Gee and Co's. large sea-going steam-ships, and has given wery general satisfaction, for by the report of the chief engineer, Mr. McAndrew, a saving of fuel is effected and the steam better sustained. Another great advantage, as reported by the master, Captain Knowles, derived from this invention is, that on running before the wind, they are never now annoyed and endangered by a dense cloud of smoke in the direction of the ship's course, which, particularly at night time, creates so much risk of collision. This apparatus is also in use on board several other steamers, viz., the Yarborough and Grimshaw, belonging to the Anglo-French Company, the Albert, of Hull, and also a number of river steam-boats. I have great pleasure in noticing also an improvement introduced on board the Queen of Scotland, another ship belonging to Messrs. Gee and Co., for the same object, by the chief engineer, Mr. Smith, and having furnaces of ample capacity, answers the purpose in a most satisfactory manner. Mr. Smith's mode consists simply in keeping a few inches off the front ends of the bars quite clear and clean from side to side of each furnace, thus admitting at the right place a sufficient amount of air. The report of the master, Captain Foster, is very satisfactory; I have witnessed also the effect of this mode on the furnaces of stationary boilers with perfect results. I have now to refer to the application of Silver's Marine Governor as applied by Mr. John Hamilton, of Glasgow. Several of these ingenious and efficient instruments are now in use on board steam-ships in the port of Hull, giving the highest satisfaction. They are so sensitive in their action, that the slightest pitching motion is at once indicated, and the steam admitted or excluded as the case may be. By the use of this governor (which is illustrated in the annexed engraving), the full power of the engines is in immediate and constant requisition, producing the effect of saving of time, saving of fuel, and preventing of accidents by what is termed racing and otherwise. The ordinary mode, in the absence of the governor, is for the engineer in stormy weather and heavy seas continually to stand at the throttle-valves, or, to save himself this trouble, to throttle the engines, and thereby when the full power of the engines is most required, it is frequently reduced to one-half or less, and consequently there is occasioned a loss of time on the voyage, and the risk of falling on to a lee shore. SILVER'S PATENT MARINE AND STATIONARY The engraving represents the Momentum Wheel Governor or "Nautical Regulator," as it is usually placed in the engine-room of a steam-ship. It consists of a momentum wheel A fixed on the boss of a pinion B, which works loosely on the spindle C, and gears into the two-toothed sectors D D. These two sectors being supported on a crosshead E, made fast to and carried with the spindle C, work in opposite directions on the pinion B; and as they are linked by the rods FF to the sliding collar G, which receives and works the forked lever H, communicate motion to the throttle valve. M M are vanes, and N is a spiral spring, both of which are adjustable. The action of the above instrument is as follows:-When the spindle of the governor or "Nautical Regulator'' is turned by the engine to which it is attached, the two-toothed sectors, which are carried on the fixed crosshead, being geared into the pinion on the momentum wheel, have the tendency to turn round on this pinion; but as they are linked to the sliding collar, they necessarily pull inwards this collar, and so compress the spiral spring, and this spring reacting on the collar, and consequently on the toothed sectors, serves to turn round the momentum wheel, while the vanes on the momentum wheel balance the action of this spring by the resistance the atmosphere offers to their progress through it. As the leverage action of the toothed sectors upon the momentum wheel pinion increases as the spring becomes distended, and vice versa, it will be seen that the reaction of the spring in propelling the momentum wheel will at all times be uniform, and as much only is required as will carry round the momentum wheel with its vanes at its proper speed, and overcome the friction of working the throttle valve and throttle valve connections. When the momentum wheel is in motion, it will rotate with the engine to which it is attached at a velocity proportioned to that at which it is fixed by the connecting gear; and while the engine from the usual causes may attempt to vary this velocity, it cannot affect the momentum wheel, but leaves it free to act upon the sliding collar, and consequently upon the throttle valve-at one time closing the throttle valve by its action in resisting any increase of velocity, and at another time opening the throttle valve by its action in resisting any decrease of velocity on the part of the engine. It will now be evident that the power of such a governor or regulator must be very great indeed, having for its agent a momentum wheel which may be increased to any dimensions, and from the powerful resisting tendency of such wheel, it necessarily follows that its sensitiveness of action must also be very great, and in exact proportion to the tendency of the engine to vary its speed; and the engine itself being the direct prime mover of the throttle valve, it also follows that the inert power of the momentum wheel increases its resistance exactly in proportion to the rapidity with which the engine varies its speed. Hence, a momentum wheel of two feet eight inches diameter, and two inches periphery, running at a speed of 180 revolutions per minute, is found to be sufficient to work with promptness and ease the largest throttle valve, and to equal the power of several men. Unlike the ordinary forms of governors, it is entirely unaffected by changes of position, and therefore perfectly adapted for marine and portable, as well as stationary steamengines. The continental papers state that preparations are being made for an Agricultural Exhibition in St. Petersburg in September, 1860. wrecks have been posted on the books at Lloyd's. During the past week no fewer than 40 total Among the more calamitous were the destruction by fire of the ship Schah Jehan. She was bound from Calcutta to the West Indies, and had on board 300 coolie emigrants. For four days every effort was made to save the ship and the unhappy creatures on board, and ultimately three rafts, crowded by 300 souls, were set adrift, and have never since been heard picked up in a very distressed condition, five days of. The masters, officers, and crew, about 60, were after, by the ship Vasco de Gama. There are, in addition, several missing vessels, respecting which the most painful forebodings are entertained. MR. DENNYS, (lek of H. M. ship Britannia, at Portsmouth, has invented a new description of life buoy, which appears to possess some decided advantages over the ordinary buoy used in the navy. Instead of the two hollow copper spheres connected by a cross-bar as used in the old life buoy, Mr. Dennys adopts an annular float, within which the balance bar works by a very simple and ingenius arrangement, the whole of which affords greater facilities for the immersed person to get a firm hold of the buoy, and, by saving exertion, of course prevents exhaustion of strength, and thus enables the person to sustain himself longer than he otherwise could do. Mr. Dennys' plan has been examined by several experienced naval officers, who have expressed themselves well pleased with it, and it will doubtless be brought to the notice of the authorities. The following is a description of Mr. Dennys' life buoy by the inventor: TAYLOR'S PATENT STEAM ELEPHANT. THE subject of steam traction on common macadamised roads and over soft ground, is now engaging the attention of the public. Taylor's patent steam elephant, a side elevation of which we here give, is a very compact and well-arranged machine for the purpose. It consists of a tubular boiler 4 ft. 8 in. long, with the fire placed in a flue, and the flame returns through a number of tubes to the chimney, which is situated at the the boiler there is no fear of any of the tubes same end as the fire-door; by thus shortening becoming uncovered during the course of the engines up steep inclines. The furnace is also adapted to the burning of wood, and is fitted funnel passes through the dome of the boiler, so with a simple smoke-consuming apparatus. The as to superheat the steam, and is provided with an efficient spark catcher. "This invention consists of a hollow copper buoy with a suspended stanchion in the centre to support the light. Two indentations, one on the upper and the other on the under surface of the buoy, and opposite each other, allow this stanchion to assume a perfectly horizontal direction to the plane of the ring when suspended; on being let go it becomes perpendicular, and is locked in that position by a catch. It is nearly impossible to capsize this buoy. Hollow copper balls suspended on the same guides or on others at the ship's quarters, connected with the buoy itself by floated lines, give an additional chance of safety to a drowning person, as, even if ten or twelve feet distant from the buoy, he may manage to draw himself to it by their aid. It may either be fired in the usual way, the present guides, slip, and percussion hammer being retained; or a friction tube may be used, firing the fuze by the weight of the buoy on being let go. Kisbee's reed life buoys may be fitted on this principle with little trouble. W. B. DENNYS." EXPLANATION OF DIAGRAMS.-Fig. 1 shows the buoy at the ship's stern; Fig. 2 shows it afloat. 4, hollow copper buoy; B, stanchion supporting light; C, weight to balance light; D, catch to secure stanchion in a perpendicular position; E, plate for the fuze and light; F. hollow copper or cork balls; G, guide rods; H, rings for guide rods; I, lines floated with corks attaching balls to buoy. It will be seen.on reference to the engraving, both engineman and steerer stand in front of the engine, which is without doubt their proper position, and both fuel and water sufficient for a distance (with a load) of about fifteen miles, are stowed away in a very compact manner. The driving cylinders are placed upright at the end of alone it will run six easily; so, taking the other expenses, including 20 per cent. per annum for depreciation of the value of the machine, we have the following result, viz., that Taylor's engine will draw a weight of 16 tons a distance of 36 miles in the 12 hours at a cost of 2s. per ton; this is two-thirds of a penny per ton per mile. It would be waste of time to enlarge upon the advantages of this mode of traction over that by animal power. It is now an established fact, and the application of the system becomes a mere matter of economical mechanical arrangement and improvement from time to time. TAYLOR AND GRIMSHAW'S PNEUMATIC APPARATUS. THE following has been submitted to us for publication:-"There may be seen at the Crystal Palace an instrument, recently patented by Messrs. Taylor and Grimshaw, of Southampton, which is calculated in a very high degree to add to our comfort and safety; it has a variety of action; perhaps its most prominent feature is its fire alarum apparatus. As such, it is capable of becoming a sideboard or bed-room ornament; it action is perfectly simple and invariable, either in a dwelling or factory, or in the hold of a ship. It may be set to any degree of temperature, when that is exceeded it indicates the fact; first, silently, then by its loud ringing alarm; or, if required, it discharges a powder cell the boiler, and drive the wheels, which are situated at the tail of the engine, and which gear into the main driving wheels, which make about 14 revolutions, while the engines are working 280. revolutions per minute. The chief part of the weight of the machine is over these wheels, which are 6 ft. in diameter, with broad peripheries, so as to give a good hold upon the ground; they are also so arranged that they will adjust themselves to work at different speeds when rounding a corner. The total weight of the machine, including fuel and water, is seven tons, and its power that of six horses; there is also no difficulty in checking its progress when going down an incline. The utility of this engine is not confined to traction purposes, as by means of clutches the engine can be disconnected from the driving gear, and can then be used for pumping, hoisting, or driving machinery; the whole machine rests on springs, and the condensed water from the cylinders, safety valves, &c., is used for heating the feed-water, so as to economise fuel as much as possible. On reference to the engraving it will be seen that A shows position of boiler; B, the gearing; C, the driving-wheel; D, steering apparatus, and E the fuel box. As to the practical working of these engines, the results have proved most satisfactory. The amount of fuel consumed when in full work is 70 lbs, and of water 28 gallons, per hour. The speed of the machine with a load is equal to about three miles per hour, although with the report of a pistol or nine-pounder, as may be required, either to alarm the inmates of a house or the neighbours of an uninhabited mill, church, or other edifice. A simple application of the hands to the sides of the machine at once sets the indicator in motion, and explains its action. A second form of its application is a ventilator. If tested in the same manner, it will open a ventilator, which will close on the removal of the hands. For common purposes, it may be set to any required temperature as may be needed for your chamber, conservatory, or barrack-room. When the required temperature be exceeded, the venti lator opens, and so remains until the desired temperature be regained. As indicative of heat, it acts in the same manner, and can in the same way be tested for sea purposes: a long tube rising from the hold of a ship, or wherever required, having at its summit on deck a simple dial, which shows at all times the heat below, giving timely warning, and averting the sad calamity of a ship on fire at sea. It is also a heat regulator, working a damper by which air is admitted more freely, or excluded from the fire. It is susceptible of a variety of other applications. The above are all easily tested and understood. The principle upon which this variety of useful application is based is the enclosure of common air within an airtight metal cylinder, having on its upper side a firmly-fixed diaphragm of india-rubber, upon which rests the spring which works the indicator. The enclosed air expands or contracts as the surrounding air becomes hotter or colder, acting in its expansion or compression on a spring which causes the indicator to show upon the dial the temperature obtained, and giving its loud warning when the dangerous degree has been attained. The apparatus in question has neither wheels nor arrangement capable of getting out of repair: no mercury or other fluid than air is used; and it would be rather difficult, without some trouble, to cause it to work inaccurately." The above account proceeds from the inventors, and may be taken as their view of an apparatus which has been favourably spoken of in the city articles of most of our newspapers during the past week, and in other places. That our readers may be able to judge for themselves of the merits of Messrs. Taylor and Grimshaw's invention we have had the annexed engraving of it, as arranged for an alarum, prepared. A is the diaphragm, B a rod which rises and falls with it, and which has a threaded portion C working into a wheel on the axle of the pointer D. The pointer D indicates the temperature on the graduated arc E, and above this is a second arc which turns upon, and may be clamped to, the axle of the pointer. Above the second arc is a disc, bell, and hammer, so arranged and connected with a weight (not shown) that by suitably adjusting the second arc the hammer may be released and caused to beat upon the bell when any given temperature is attained. ARTESIAN WELL AT WOLVERHAMPTON: "ON AN ARTESIAN WELL IN THE NEW RED SANDSTONE AT THE WOLVERHAMPTON WATERWORKS." By J. F. BATEMAN, Esq". THE town of Wolverhampton has been up to a recent period supplied with water produced by two deep shafts-one sunk about 300 feet deep into the lower New Red or Permian measures, and the other to a somewhat similar depth in the New Red Sandstone proper. From both of these wells a large quantity of water was anticipated by the engineers who advised their construction, but their yield is under 200,000 gallons a day each, the water being pumped in one case from a depth of above 180 feet, and in the other 246 feet. The quantity thus yielded being insufficient for the supply of the district, new works have been constructed which I have just completed for bringing water from the river Worth at Corford Bridge, about nine miles from Wolverhampton and three from Shiffnall, in the county of Salop. The works are constructed for the supply of 2,000,000 gallons per day, and the water has to be forced to a height of 500 feet for the supply of the town. The river Worth at the place at which the pumping works are constructed is not more than 40 or 50 feet above the Severn, which it joins at Bridgmouth, about eight or 10 miles distant. It may, therefore, be considered to be at the bottom of a basin, little elevated above the sea. From the character of the surrounding hills and the inclination of the beds of the New Red Sandstone, it appears to me very likely that, although the wells • British Association, 1859, which had previously been sunk on the high plateau of Wolverhampton had proved compara tive failures, a considerable quantity of water might be found in the sandstone at Corford Bridge, and that possibly some might rise to the surface and flow as an artesian well. I therefore obtained the sanction of the directors of the company to sink a bore hole for the purpose of ascertaining the fact. In some parts of the country, as in Cheshire and Lancashire on the shores of the Mersey, the New Red Sandstone is very clearly divided into four distinct portions, consisting of an upper hard mass about 300 or 400 feet thick, a soft mass about the same thickness, a second hard mass, and a lower soft mass, all of pretty much the same thickness. In the neighbourhood of Wolverhampton and Shiffmall, these distinctions are not so clearly exhibited, but I had reason to believe, from the portion of the works, that a bore hole of about 200 feet in depth would pierce the hard rock on which they were situated and reach the soft rock beneath. The bore hole was commenced twelve inches in diameter, and continued at that size for seventy feet in depth, when it was diminished to seven inches, and continued for 190 feet, one being a total depth from the surface of 260 feet. The first water was met with at a depth of 25 feet 4 inches, and from that time it rose to the surface and flowed over an artesian spring, increasing in quantity as the depth increased, till the boring was discontinued, at which time it amounted to about 210,000 gallons per day. The following table will show the manner in which the water increased :— Depth below Yield in surface. 21 hours. Ft. in. Galls. 25 4 2,880 3,553 Yield in 24 hours. Gall. 37,023 43,200 61.899 71,055 29 4 37 6 3,602 Depth below surface. Ft. in. 119 O 123 6 142 4 86.400 129,600 130,896 221 7 163,200 183,690 101 O 111 2 ... 260 O 200,830 25,920 32,400 Throughout the whole depth of boring the rock varied little in character. It was nearly all hard rock. Sometimes very hard, with occasional beds of softer stone. For the last forty feet or so, the soft beds were thicker, but otherwise there was little change from top to bottom. The greatest increase of water took place at 214 feet and 227 in depth, at each of which depths there was an increase of 20,000 gallons per day. The soft rock I anticipated was not met with at the depth I expected, but sufficient was done to prove the abundance of water. A large bore hole, which would permit the descent of a larger column of water, would materially increase the produce as an artesian well, while a shaft sunk thirty feet or forty feet deep, and exhausted to that depth by pumping, would yield a very considerable quantity. As the whole rock is charged with water to the level of the river which forms its natural outlet, and as the boring shows that the lower beds receive their supplies from distant sources, the supply to be obtained may reasonably be expected to be inexhaustible within the limits of that which is due to the percolation of the rain upon the collecting area. On Saturday the great bell of Westminster sounded for the last time, and while in the very act of striking Big Ben became dumb for ever. The bell is even more hopelessly cracked than its ill-fated predecessor. Such a weary deal has to be done before Ben's mutilated fragments find their way to the melting pot, and still more before the renovated mass is again restored to its lofty dwelling, that, even taking a sanguine view of things, we think, with the Times, that at the least a clear twelvemonth must elapse before the voice of the great bell can again be heard booming over the great province of houses in which it is to regulate the laws of time. The cause of its destruction is explained by Mr. Loseby on another page, ON A SAFETY CAGE FOR MINERS. THE object of the present invention is to save the lives of miners who may happen to be in the cage at a time when the rope to which it is attached gives way. It fortunately happens that almost every shaft is provided with a pair of strong wooden rods, called guide-rods, which extend from top to bottom. These are placed on opposite sides of the shaft with the cage between them. The latter is furnished with iron shoes or slides at top and bottom, which loosely embrace the guide-rods and constrain it to keep one path in ascending and descending. To cause the cage, on the failure of the winding tackle, to cling to these guide-rods is the object sought in all safety cages. My plan for effecting this is a mere adaptation of an instrument well known to miners-the key or wrench used for raising and lowering the boring rods. This little instrument has never been known to lose its hold. It supports 100 fathoms of rods with the same tenacity that it does ten. Indeed, the greater the weight it is required to hold, the firmer is the gripe. It therefore is admirably calculated to support the cage, which, in addition to its own weight and load, may have to bear the weight of some hundred fathoms of rope precipitated on it from above. To adapt this instrument to the cage, a slight modification of the upper shoes and slides is all that is necessary. These shoes or slides are, as usual, two in number, and placed on the opposite sides of the cage and in opposite directions. Each of them has a single bolt or stud, by which it is attached to the cage, and around which it turns ; a long arm, to the extremity of which the winding chain is attached; a stop, which prevents the arm from being pulled above the horizontal line; and a spring, which lowers it when the winding chain is slack. From this description it is easily seen that in the event of the rope or gearing giving way, the springs so tilt the shoes or slides that they immediately seize hold of the guide-rods, in the same manner as the boring key in the hands of a miner lays hold of the boring rods, and with the same tenacity of gripe; and although the rope should come down on the top of the cage, the only effect would be to cause the shoes to dig deeper into the guide-rods, and thus to make the hold more secure. STRAIGHTENING A CHIMNEY STALK. THE operations for restoring the colossal chimney at Port Dundas to a perpendicular and safe position are now successfully completed. This was accomplished by sawing several of the mortar beds between the courses on the side from which back by its own weight, without the application the chimney leaned, thereby allowing it to come of any external force. Only one draft was cut at have endangered the stability of the building, and a time, to guard against any shock which might by keeping the saws wet a bed of mortar was prepared for the superincumbent weight to settle down upon. 12 cuts were made in this manner, rally set before the saws had passed through half on different parts of the structure, which geneof the circumference, particularly in those made nearest the ground, where the weight was greatest. We have to congratulate the proprietor and Mr. Duncan Macfarlane, architect, by whose advice this method was adopted, on the success of their undertaking. The principal dimensions of the chimney are:-Total height, 468 feet; from surface to top of cope, 454 feet; outside diameter at foundation, 50 feet; at surface, 34 feet; at cope, 14 feet. According to calculations made by Professor Rankine, the building, independent of the adhesion of mortar, is capable of sustaining with safety a lateral pressure of 66 lbs. per superficial foot at its weakest point, being 11 lbs, more than the force of the greatest storm registered in this country.-North British Daily Mail. * British Association, 1859, |