In 1696, Mr Everard, balance-maker to the Exchequer, weighed before the Commissioners of the House of Commons 2145.6 cubical inches, by the Exchequer standard foot, of distilled water, at the temperature of 55 deg. of Fahrenheit, and found it to weigh 1131 oz. 14 dts. Troy, of the Exchequer standard. The beam turned with 6 grs. when loaded with 30 pounds in each scale. Hence, supposing the pound averdupois to weigh 7000 grs. Troy, a cubic foot of water weighs 62-1/2 pounds averdupois, or 1000 ounces averdupois, wanting 106 grains Troy. And hence, if the specific gravity of water be called 1000, the proportional specific gravities of all other bodies will nearly express the number of averdupois ounces in a cubic foot. Or more accurately, supposing the specific gravity of water expressed by 1. and of all other bodies in proportional numbers, as the cubic foot of water weighs, at the above temperature, exactly 437489.4 grains Troy, and the cubic inch of water 253.175 grains, the absolute weight of a cubical foot or inch of any body in Troy grains may be found by multiplying their specific gravity by either of the above numbers respectively. By Everard's experiment, and the proportions of the English and French foot, as established by the Royal Society and French Academy of Sciences, the following numbers are ascertained. Paris grains in a Paris cube foot of water = 645511 English grains in a Paris cube foot of water = 529922 Paris grains in an English cube foot of water = 533247 English grains in an English cube foot of water = 437489.4 English grains in an English cube inch of water = 253.175 By an experiment of Picard with the measure and weight of the Chatelet, the Paris cube foot of water contains of Paris grains = 641326 By one of Du Hamel, made with great care = 641376 By Homberg = 641666 These show some uncertainty in measures or in weights; but the above computation from Everard's experiment may be relied on, because the comparison of the foot of England with that of France was made by the joint labours of the Royal Society of London and the French Academy of Sciences: It agrees likewise very nearly with the weight assigned by Mr Lavoisier, 70 Paris pounds to the cubical foot of water. No. IX. TABLES _for Converting Ounces, Drams, and Grains, Troy, into Decimals of the Troy Pound of 12 Ounces, and for Converting Decimals of the Pound Troy into Ounces, &c._ I. _For Grains._ Grains = Pound. 1 .0001736 2 .0003472 3 .0005208 4 .0006944 5 .0008681 6 .0010417 7 .0012153 8 .0013889 9 .0015625 10 .0017361 20 .0034722 30 .0052083 40 .0069444 50 .0086806 60 .0104167 70 .0121528 80 .0138889 90 .0156250 100 .0173611 200 .0374222 300 .0520833 400 .0694444 500 .0868055 600 .1041666 700 .1215277 800 .1388888 900 .1562499 1000 .1736110