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Knight's Mechanical Encyclopedia (ed. Knight), A. (search)
ini was composed, as is seen in the Dedication, at the court of the Saljuke Sultan Sanjar, who reigned over a large part of the ancient Khalifate of Baghdad from A. D. 1117 to 1157. The areometer of Pappus is very similar to the Volumeter of Gay Lussac. Gay Lussac' scale areometer consists of a cylindrical glass tube in the lower part of which a ball b is blown, and, being continued, finally terminates in another ball c. The latter is filled with shot or mercury, to cause the instrument to sink vertically in distilled water to a certain point, the zero. The specific gravity of a liquid is ascertained by the depth of depression, its weight being equal to that of the liquid displaced. It is a form of hydrometer. Gay Lussac's areometer A-re-o-sty′los. An intercolumniation of four diameters width. Argand Gas′–burn-er. The Argand Gas-burner has a circular series of holes on the upper edge of a cylindrical chamber, having a central aperture to allow access of air to t<
Knight's Mechanical Encyclopedia (ed. Knight), B. (search)
794. Balloons were also employed by the French in the Italian campaign of 1859, at Solferino; and subsequently, during our own civil war, a small corps of balloonists was attached to the Army of the Potomac. The celebrated French chemist, Gay Lussac, in 1804 reached the hight of 23,040 feet, and carried up with him the necessary means for making scientific observations on the character and properties of the atmosphere at that great hight. This was for many years considered the most remarkor measuring or transferring small quantities of liquid. It sometimes has a stop-cock, and the discharge through its small orifice is sometimes checked by the finger placed on the opening above, as in the velinche or pipette. As invented by Gay Lussac, for dividing a fluid into minute portions, it consists of a large tube, graduated to 1/100 and 1/1000, and a smaller parallel connected tube. Bur-gage. （Metal-working.) A plate perforated with holes of graduated sizes, whose numbers de
Knight's Mechanical Encyclopedia (ed. Knight), C. (search)
as continually maintained, as in the Magian, Egyptian, and Grecian temples. Candles are of several varieties: — 1. Paraffine; obtained from the distillation of coal at a low heat, also from lignite, peat, and wood. Frequently combined in candles with sperm and stearine See paraffine. 2. Spermaceti. Usually of wax and spermaceti. These are molded. 3. Composition. Mixtures of spermaceti, tallow, with a little resin or wax, in various proportions. 4. Stearine. In June, 1825, Gay Lussac obtained a patent in England for candles made of the stearic acid of tallow, lard, or cocoanut oil. The fatty acids are separated from the glycerine by caustic lime, the fat, lime, and water being boiled and stirred together until the mixture is fully saponified. The lime is then saturated by agitation with dilute sulphuric acid, which forms a solid sulphate of lime, and sets the fatty acids at liberty; the latter rise to the surface, and are decanted from the limy sediment. The trace
Knight's Mechanical Encyclopedia (ed. Knight), H. (search)
211.160471.448731.924 221.169481.462741.949 231.178491.476751.974 241.188501.490762.000 251.197511.505 For Liquids lighter than Water. 101.00027.89644.811 11.99328.89045.807 12.98629.88546.802 13.98030.88047.798 14.97331.87448.794 15.96732.86949.789 16.96033.86450.785 17.95434.85951.781 18.94835.85452.777 19.94236.84953.773 20.93637.84454.768 21.93038.83955.764 22.92439.83456.760 23.91840.83057.757 24.91341.82558.753 25.90742.82059.749 26.90143.81660.745 In Gay Lussac's centigrade hydrometer the specific gravity of a liquid heavier than water is found by subtracting the indication from 100 and dividing 100 by the remainder; if lighter than water, add the indication to 100 and divide 100 by the sum, thus 10° below 0° = 100/90=1.111 specific gravity; 10° above 0° = 100/110=0.909 specific gravity. The hydrometer of Brix is that legally used in Prussia; to ascertain the specific gravity the constant number, 400, is divided by 400 + the indication for liq
Knight's Mechanical Encyclopedia (ed. Knight), P. (search)
ight, or the whole surface would blacken, as a necessary consequence, and neither Wedgwood nor Davy ever overcame this difficulty, or found means to fix such photographs and render them permanent. To Wedgwood, however, must be accorded the honor of having been the first to produce a photograph, in the artistic and technical sense of the word. Dr. Thomas Young, the originator of the undulatory theory of light, published in 1804 some important researches on the chemical rays. In 1809, Gay Lussac and Thenard made the exceedingly valuable observation, that a mixture of chlorie and hydrogen did not combine in the dark, whereas in diffused daylight they did so rapidly, and in sunlight with explosion. Berard, in 1812, made a comprehensive and valuable series of investigations, which was reported on by Berthollet, Chaptal, and Biot, acting as a commission. By them the solar emanations were first regarded as consisting of calorific, colorific, and chemical rays. In 1814, Joseph Ni
Knight's Mechanical Encyclopedia (ed. Knight), S. (search)
fact soon suggested a practical application. In 1823 a complete account of the labors of M. Chevreul was published. The steps which led to the great manufactures and commercial undertakings, such as the Price Candle Factory, were made by Gay-Lussac and Chevreul in 1825. They first thought of forming the fatty acids by saponifying the fats by alkalies and the alkaline earths, decomposing by acid, and separating the solid and liquid parts by pressure. In the earlier processes the expense of plaited wick, put the industry upon a firm footing. To quote farther from Professor J. Lawrence Smith:— A second advance in this industry was the use of sulphuric acid to decompose the fats; this plan originated also with Chevreul and Gay-Lussac, but was not successfully carried out until combined with the distillation of the fatty acid after the decomposition, — a method first executed by Dubrunfaut, and successfully carried out by Coley, Jones, and Wilson, and subsequently perfected by
Knight's Mechanical Encyclopedia (ed. Knight), T. (search)
am withdrawn. Tube-pouch. The artilleryman's leather pouch for carrying friction-primers. It has two loops, by which it is fastened to the belt. The priming-wire and gunner's gimlet are carried with it. Tube-re-tort′. A retort made from a glass tube, closed at one end, and sometimes having a swelled bulb. a (Fig. 6741), Clark's retort, and b, receiver, for the distillation and condensation of small quantities of acid. c, Faraday's retort and receiver in one piece. d, Gay Lussac's bent-tube retort, used when a solid is to be heated in a gas confined over mercury. Tube-scal′er. （Steam.) A tool for removing soot and incrustation from the insides of flues of steam-boilers. See tube-cleaner. Tube-retorts. Tube-scrap′er. （Steam.) An implement for removing rust, sediment, etc., from boiler and other tubes. The example is adapted for attachment to piece of gaspipe as a handle. The blades, which are curvilinear in outline, are expanded by spring