The penetration in other kinds of earth and stone may be obtained by using the coefficients given for the other tables. For woods, use for beech and ash 1, for elm 1.3, for white pine and birch 1.8, and for poplar 2. 144 grains of powder in a musket, at 5 yards' distance, will project a ball 3 inches into seasoned white oak, and 100 grains in a rifle, at the same distance, 2.05 inches. * From the West Point Foundry Association at Cold Spring, N. Y. Other experiments have given .2613 as the weight of a cubic inch. +Ulster Iron Company, Saugerties, N. Y. From Phelps, Dodge, & Co.'s Works, in Derby, Conn. SIZES OF NUTS, EQUAL IN STRENGTH TO THEIR BOLTS. Diameter of bolt in inches. of nut in inches. in inches. NOTE.-The depth of the head should equal the diameter of the bolt; the depth of the nut should exceed it in the proportion of 9 or 10 to 8. Diam. in inches, No. of threads, Diam. in inches, SCREWS. TABLE showing the Number of Threads to an Inch in V thread Screws. 20 18 16 14 12 11 10 9. 8 7 7 6 21 21 21 333 The depth of the threads should be half their pitch. The diameter of a screw, to work in the teeth of a wheel, should be such that the angle of the threads does not exceed 10°. Temperature. TABLE of the Strength of Copper at different Temperatures. Strength in lbs. Temperature. Strength in lbs. Temperature. Strength in lbs. 23 cubic feet of sand, or 18 cubic feet of earth, or 17 cubic feet of clay, make a ton. 18 cubic feet of gravel or earth before digging, make 27 cubic feet when dug. COAL GAS. A chaldron of bituminous coal yields about 10.000 cubic feet of gas. Gas pipes inch in diameter supply a light equal to 20 candles. 1.43 cubic feet of gas per hour give a light equal to one good candle. ALCOHOL Is obtained by distillation from fermented liquors. Proportion of Alcohol in 100 parts of the following Liquors: Ashes, 2 parts) Mixed with oil, will resist the weather equal to Clay, 3 Sand, 1 marble. HYDRAULIC CEMENT. A barrel contains 300 lbs., equal to 4 struck bushels. BROWN MORTAR. One third Thomaston lime, Two thirds sand, and a small quantity of hair. |