ADDENDA AND CORRIGENDA. PAGE 63. In reducing Cailletet's experiments, 000 0026 should have been added instead of 000 0039. PAGE 77. Add-Violle's determination of velocity of sound is 331 10±0.1. Ann. de Chim. XIX. March, 1890. PAGE 176, line 10. For Wuilleumeier, 1890, read Wuilleumier, 1890, Lippmann method. At end of page 164, add-Expressing C in amperes, R in ohms, and T in seconds, the heating effect in gramme-degrees is CRT/42=24C2RT. PAGE 35. Mr. Chaney's determination here quoted was not intended as a determination of the density of water, but of the apparent weight of water when weighed in air of density 001 216 84 against brass weights of density 8·143. The correcting factor for deducing the weight in vacuo or true density is 1001 0687, which will change the value 998 752 obtained in the text into 999 82, to compare with Tralles' .999 88. Mr. Chaney's result is for distilled water deprived of air, and Tralles' appears to be for ordinary distilled water. According to results recently obtained by the Vienna Standards Commission (Wied. Ann. 1891, Part 9, p. 171), water deprived of air has the greater density, the difference being 000 0032 at 0° C., and 000 0017 at 62° F. These differences are too small to affect the above comparison. REDUCTION TO AND FROM C.G.S. MEASURES. ACCORDING to Col. Clarke's comparisons of standards of length (printed in 1866), the metre is equal to 1.09362311 yard, or 3.2808693 feet, or 39.370432 inches, the standard metre being taken as correct at 0° C., and the standard yard as correct at 163° C. Hence the inch is 2.5399772 centims., the foot 30.479726 centims., the square inch 6·4514842 square centims., and the cubic inch 16-3866227 cubic centims. According to the U.S. Coast Survey Bulletin, No. 9, 1889, a more probable value of the metre is 39.36980 inches. According to the comparison made by Professor W. H. Miller in 1844 of the "kilogramme des Archives," the standard of French weights, with two English pounds of platinum, and additional weights, also of platinum, the kilogramme is 15432-34874 grains, of which the new standard pound contains 7000. Hence the kilogramme would be 2.2046212 pounds, and the pound 453.59265 grammes. Three standard pounds, one of platinum-iridium and the other two of gilded bronze, belonging to the Standards Department, were compared, in 1883, at the Bureau International des Poids et Mesures, with standards belonging xiii |