Fig. 9. A WIRE STAND.

Fig. 10. AN APPARATUS for showing the diminution effected in the volume of hydrogen and oxygen gases, by their slow combustion. The jar inverted in ff, is filled with oxygen gas; the large bladder with hydrogen; to this bladder it will be seen is attached a tube with a long brass pipe bent: a stop-cock is attached, d. The bladder being pressed, a stream of gas issues through the pipe, which may be set on fire, and cautiously brought under the jar of oxygen; the combustion being continued for a certain time, the water will rise gradually within the jar in proportion to the consumed oxygen.

Fig. 11. This figure 1epresents the different parts of the apparatus required for measuring the quantity of elastic fluid given out during the action of an acid on calcareous soils. The bottle containing the soil is represented at a. The bottle containing the acid furnished with a stopcock. c, The tube connected with a flaccid bladder d. f, A graduated measure. e, The bottle for containing the bladder. When this instrument is used, a given quantity of soil is introduced into a. b is filled with muriatic acid diluted with an equal quantity of water, and the stop-cock being closed is connected with the upper orifice of a, which is ground to receive it. The tube c is introduced into the lower orifice of a, and the bladder connected with it, placed in its flaccid state in e, which is filled with water. The graduated measure is placed under the tube of e. When the stoppercock of b, is turned, the acid flows into a, and acts upon the soil; the elastic fluid generated passes through e into the bladder, and displaces a quantity of water in e equal to it in bulk; and this water flows through the tube into the graduated measure, the water in which gives by its volume the indication of the proportion of carbonic acid disengaged from the soil; for every ounce measure of which two grains of carbonate of lime may be estimated. See SOIL and AGRI

CULTURE.

Fig. 12. A COMMON NOOTH'S APPARATUS for impregnating water with gas. The lower vessel, c, contains the effervescing materials; d, represents a ground stopper closing an orifice, by which additional materials may be put into the lower vessel. b, The middle vessel opened both above and below to the neck of the lower vessel, which receives the inferior neck of the middle vessel; this connexion is so contrived, that gas may pass up, but fluid cannot return. e, A cock to draw off the contents of b; the upper vessel, a, is fitted by grinding into the upper neck of the middle vessel; its inferior part consists of a tube that passes almost as low as the centre of the middle vessel. A ground stopper closing the upper orifice. When this apparatus is to be used, the effervescent materials are put into the lower vessel; the middle vessel is filled with pure water, and put into its place; and the upper vessel is filled and likewise put into its place. The consequence is, that the carbonic acid gas, passing through the valve at h, ascends into the upper part of the middle vessel b, where by its elasticity it reacts on the water, and forces part up the tube into the vessel a; part of the common air in this last being compressed, and the rest escaping by the stopper, which is made of

a conical figure that it may be easily raised. As more carbonic acid, or any other gas is extricated, more water rises, till at length the water in the middle vessel falls below the lower orifice of the tube. The gas then passes through the tube into the upper vessel, and expels more of the coinmon air by raising the stopper. In this situation, th water in both vessels being in contact with a body of carbonic acid gas, it becomes strongly impregnated with this gas after a certain time, This effect may be hastened by taking off the middle and upper vessels together and agitating them.

Fig. 13. A BLOW-PIPE.

Fig. 14. VIVID COMBUSTION IN OXYGEN GAS. Fig. 15. A BOTTLE AND TUBE for directing a small stream of water on any object. This purpose, says Dr. Henry, from whom we take the figure, may be very conveniently effected by fixing a glass tube of small bore two or three inches long, and bent at one end to an obtuse angle, into a hole bored in a cork, which may be used as the stopper of an eight ounce phial filled with water. On inverting the vial, and grasping the bottom of it, the warmth of the hand expels either a few drops, or a small stream of water which may be directed on any minute object. When the flow ceases it may be renewed if required, by setting the bottle for a moment with its mouth upwards (which admits a fresh supply of cool air), and then proceeding as before.

Fig. 16. The common APPARATUS used for transferring air or gas from one vessel to another. a, A wooden tub. k, k, A shelf fixed in it. When the apparatus is used, the tub is to be filled with water, about one inch above the shelf. b, g, f, are glass jars inverted upon the shelf; these being filled with water, and thus inverted on the shelf, will remain so filled till displaced by directing a stream of air or gas into them, which, by its superior levity, will rise in the glass, and press upon and dislodge part of the

water.

Fig. 17. A GAS-HOLDER. a and c, Two short pipes, terminated by cocks. b, A pipe passing through the middle of the cover, reaching within half an inch of the bottom of the apparatus. The vessel is first filled with water through the funnel, at the top of the apparatus; the cock a being left open and c shut. The gas from the gasometer is to be directed into the aperture a. The cock c is now opened, and b shut, and the vessel will thus be filled with gas by the expulsion of the water at c; when this no longer flows the vessel is full of the gas, and now all the cocks are to be shut till the contents of the air-holder are required for use. See for description and figures of improved gas-holders, the 13th, 24th, 27th, and 44th vols. of the Philosophical Magazine.

EXPLANATION OF PLATE V.

Fig 1. A LAMP FURNACE, improved by Mr. Accum. It consists of a brass rod, screwed to a foot of the same metal, loaded with lead. On this rod, which may be unscrewed in the middle, slide three brass sockets, terminating in brass rings, which rings are for supporting alembics, flasks, retorts, &c. By means of a thumb-screw acting on the rod of the lamp, each of the brass

rings may be placed according to pleasure. Below these rings is a fountain lamp, on Argand's plan, which also slides on the main brass rod by means of a socket and thumb-screw. This lamp may be used for producing any degree of heat that the operator requires, from a very gentle one up to the high temperature requisite for distilling mercury.

Fig. 2. INSTRUMENT FOR DIRECTING THE VAPOR OF ALCOHOL ON FLAME. a, A hollow sphere for containing alcohol, resting upon a shoulder in the ring o. b, A bent tube with a jet at the end, to convey the alcohol in the state of vapor to the flame at 9; this tube is continued in the inside up to c, which admits of a being nearly filled without any alcohol running over. d, A safety valve, the pressure of which is determined at pleasure, by screwing higher or lower on the pillar e, the two milled nuts ƒ and g, carrying the steel arm h, which rests on the valve., An opening for putting in the alcohol. k, The lamp which adjusts to different distances from a, by sliding up or down the two pillars 1, 1. The distance of the flame q from the jet is regulated by the pipe which holds the wick being a little removed from the centre of the brass piece m, and of course revolving in a circle. n, The mahogany stand.

Fig. 3. Represents the COMMON LARGE STILL, used for the distillation of spirits. a, The body. b, The head. d, A spiral pipe, called the worm of the still, which passes through a tub of cold water, and condenses the vaporous material, which then comes out in a fluid form at e.

It is evident that the wider and more shallow the bottom of the still, so will be its power of effecting a good deal in a short time, as the whole bottom of the vessel may be subjected to heat, and thus vaporisation speedily and copiously produced. This principle has been acted on to such an extent, that a still of the capacity of forty gallons in the body, and three in the head, charged with sixteen gallons of wash, can be worked 480 times in twenty-four hours.

Fig. 4. Presents a vertical section of this still. 4, The bottom, joined to b, the shoulder, with

ABSORPTION of heat, 245.

ACADEMY, Parisian, 362.

ACETATE of alumina, 1480.

solder or rivets, or screws and lute. c, The turned up edge of the bottom, against which, and on a level with a, the brick work of the coping of the flue rests, preventing the flames from jetting up to touch c. d, The discharge pipe. ee, The body of the still. f, Section of the central steam escape pipe. g, Section of one of the lateral steam escape pipes. h, Outside view of another. iiii, Inferior apertures of lateral steam pipes. kkkk, Their superior apertures., Bottom scraper, or agitator, which may be either made to apply close to the bottom, or to drag chains. m, The upright shaft of this engine, as it is called. n, The horizontal wheel, with its supporters. o, Its vertical wheel. p, Its handle and shaft. 9, Support of the shaft. r, Froth and ebullition jet breaker, resting on the cross bar s. t, Its upright shaft. u, Its cupmouthed collar, filled with wool and grease, and held down by a plate and screws. v, General steam escape pipe, or head. The charge pipe, and the sight hole, for the man who charges it to see when it is sufficiently full, are not seen in this view.

Fig. 5. A FUNNEL for introducing liquids into retorts, so as not to interfere with their necks.

Fig. 6. Another representation of a Woulfe's apparatus, with the supplying tube represented at h. See the other figures.

Fig. 7. A BRASS PRONG, with a wooden handle for holding an evaporating glass over a lamp. Fig. 8. SECTION OF AN EVAPORATING DISH. Fig. 9. A SEPARATOR, for separating liquids of different specific gravities. a, A ground stopper. b, A glass stop cock. When the lightest of two liquids has risen completely to the top, the heaviest may be let out by opening the stop cock, and again shutting it when all the heavy liquid has passed out.

Fig. 10. COMMON TROUGH, with an inverted jar for collecting gas, with a retort appended, containing the materials from which the gas is supplied.

Fig. 11. A PLAIN RETORT.

Fig. 12. AN ALEMBIC, WITH A RECEIVER ATTACHED TO IT.

Ammonia, 1478. Lead,

Po

Baryta, 1480. Copper, 696. Iron, 735. 136, 768. Lime 1479. Magnesia, 1480. tassa, 1470. Soda, 1471. Strontia, 1480. Tin, 751. Zinc, 807.

ACETIC acid, 1138. How procured, 1139. Composition of, 1144. Properties of, 1146. Ether, 1528. ACETOUS acid, 1142.

Formic, 1618. Gallic, 1188. Hydriodic, 363. Hydrocloric, 355. Hydrocyanic, 527. Hydrofluoric, 367. Hydrophosphorous, 455. Hydrosulphurous, 455. Hydro-thionic, 522. Hydro-xanthic, 546. Hypo-nitrous, 387. Hypo-sulphuric, 455. Hypo-sulphurous, ib. Hypo-phosphorous, 422. Igasuric, 1254. Iodic (oxiodic), 333. Iodous, 334. Kinic, 1252. Laccic, 1240. Lactic, 1612. Lithic, 1607. 1679, et seq. Malic, 1179. Manganesic, 855. Meconic, 1253 Mellitic, 1232. Molybdic, 902. Molybdous, ib. Moroxylic, 1217. Muriatie, 355, et seq. Nitric, 388, et seq. Nitro-muriatic, 394. Nitrous, 385, et seq. Oxalic, 1151. Oxiodic, 333. Perchloric, 328. Pernitrous, 387. Phosphoric, 423, et seq. Phosphorous, 420, et seq. Prussic, 527. Prupuric, 1608. Pyro-uric, 1609. Rosacic, 1610. Saclactic, 1614. Sebacic, 1615. Selenic, 461. Stibic, 829. Stibious, ib. Suberic 1224. Succinic, 533. Sulpho-cyanic, 533. Sulphureted chyazic, 533. Sulphuric, 446, et seq. Sul