Comparative Cohesive Force of Metals, Woods, and other substances, Wrought Iron (medium quality) being the unit of comparison, or 1; the cohesive force of which is 60000 lbs. per inch, transverse area. Copper, cast, Silver, cast, .66 Mahogany, best, .36 66 wire, .68 Maple, .18 Steel, soft, 2.00 Oak, Amer., 2.25 Pine, pitch, .20 Tin, cast block, .083 Sycamore, .22 Zinc," 66 sheet, .043 Walnut, .27 Willow, .75 Ivory, .50 Whalebone, .83 Marble, .30 .22 .27 .13 .15 Silver 5, 66 1, .80 Glass, plate, .16 .05 Hemp fibres, glued, 1.53 Slate, .20 The strength of white oak to cast iron, is as 2 to 9. To determine the weight, or force, in pounds, necessary to tear asunder a bar, rod, or piece of any of the above named substances, of any given transverse area: RULE.-Multiply the comparative cohesive force of the substance, as given in the table, by the cohesive force per square inch, area of cross section (60000 lbs.) of wrought iron, which gives the cohesive force of 1 square inch area of cross section of the substance whose power is sought to be ascertained, and the product of 1 square inch thus found, multiplied by area of cross section, in inches, of the rod, piece, or bar itself, gives the cohesive force thereof. Alloys having a tenacity greater than the sum of their constituents. Swedish copper 6 pts., Malacca tin 1; tenacity per sq. inch, 64000 lbs. Chili copper 6 pts., Malacca tin 1; Japan copper 5 pts., Banca tin 1; Common block-tin 4 pts., lead 1, zinc 1; tenacity per sq. in., 13000 lbs. Malacca tin 4 pts., regulus of antimony 1; " Block-tin 3 pts., lead 1 part; Block-tin 8 pts., zinc 1 part; Zinc 1 part, lead 1 part; 66 66 12000 " 10000" Alloys having a density greater than the mean of their constituents. GOLD with antimony, bismuth, cobalt, tin, or zinc. SILVER with antimony, bismuth, lead, tin, or zinc. COPPER with bismuth, palladium, tin, or zinc. PLATINUM with molybdinum. PALLADIUM with bismuth. Alloys having a density less than the mean of their constituents. GOLD with copper, iron, iridium, lead, nickel, or silver. SILVER with copper or lead. IRON with antimony, bismuth, or lead. TIN with antimony, lead, or palladium. NICKEL with arsenic. ZINC with antimony. LINEAR DILATION OF SOLIDS BY HEAT. Length which a bar heated to 212° has greater than when at the tem perature of 32°. NOTE.To find the surface dilation of any particular article, double its linear dilation, and to find the di ation in volume, triple it. To find the elongation in linear inches per linear foot, of any particular article, multiply its respective linear dilation, as given in the TABLE. by 12. MELTING POINT OF METALS AND OTHER BODIES. Lime, palladium, platinum, porcelain, rhodium, silex, may be melted by means of strong lenses, or by the hydro-oxygen blowpipe. Cobalt, manganese, plaster of Paris, pottery, iron, nickel, &c., at from 2700° to 3250° Fahrenheit; others as follows: NOTE. - The power of a body to reflect heat is inverse to its power of radiation. BOILING POINT OF LIQUIDS. 19 20 100 12 100 12 16 NOTE.-Barometer at 31 inches, water boils at 2130.57; at 29, it boils at 2100.38; at 28, it boils at 2080.69; at 27, it boils at 2060.85, and in vacuo it boils at 880. No liquid, under pressure of the atmosphere alone, can be heated above its boiling point. At that point the steam emitted sustains the weight of the atmosphere. EXPANSION OF FLUIDS BY BEING HEATED FROM 32° TO 212°, F. NOTE. Different woods have a conducting power in ratio to each other, as is their respective specific gravities, the more dense having the greater. Quantity per cent. by weight of Nutritious Matter contained in different articles of Food. per ct. Articles. 93 Meats, avg., 92 Potatoes,. 89 Beets, 85 Carrots, 83 Cabbage,. 88 Greens, per ct. 74 35 25 14 10 7 Rye, 79 Turnips, white, Specific gravity, and quantity per cent., by volume, of Absolute Alcohol contained, necessary to constitute the following named unadulterated articles. Quantity per cent., by volume, (general average) of Absolute Alcohol contained in different pure or unadulterated Liquors, Wines, &c. is The weight, in air, of a cubic inch of Proof Spirits, at 60° F., 233 grains; therefore, an inch cube of any heavy body, at that temperature, weighing 233 grains less in spirits than in air, shows the spirits in which it is weighed to be proof. If the body lose less of its weight, the spirit is above proof,- if more, it is below. |