66 JVIEMOIRS OF THE XATIONAL ACADEMY OF SCIENCES. 



more water tbau the liydrate H^ SO^. (Muspratt, vol. (i, 357.) This scale appears in Bull. Soc. 

 IikI. (le Miilliouse, 1872; Muspratt, 187!l, vol. (5, 359. 



(4) Gilpin. 6(io = 1.848. The mark 10° was found by a 10 per cent, salt solution at 10° R. 

 (Wagner, Jabresb., 186!>, vol. 15, 236.) Tbis scale appears in Henry, 1810; Cbiklreii, 1819; Ann. 

 de Chimie, vol. 23, 1797; Haudwiirterbucb, vol. 2, 1; Bacbe & McCullob, 1S4S; Knapp, Chem. 

 Tecb., vol. 1, part 5; Journal de Pbysique, 1797. 



(5) French Codex (Holland). 6Co = 1.847. In the Holland scale, the lo^ was obtained by a 10 

 l)er cent, common salt solution at 10° R. (Bacbe & McCullob. Reports on Sugar and Hydrome- 

 ters, 1848, 84.) Tbis scale appears in U. S. Dispensatory, 5tb, 7tb, 8tb, lltb, 12tb, 13tb, and 14th 

 editions; Pbarmacopiea Batava, 1805; Bacbe & McCullob, 1848; Neues Handworterbucb, 1871; 

 Dingler's Polyt. Journal, 1870. 



(6) H. A. Mott, jr. 66o=1.8461. Was deduced by Doctor Pj le, of Philadelphia, and the table 

 calculated to 0.5 by Doctor Mott. (Letter from Dr. M. to Dr. C. F. C, Nov. 8, 1881.) This scale 

 appears in Mott, Chemist's Manual, 1877. 



(7) Daltou. 660=1.8460. The poiat 66° was obtained in sulphuric acid of specitic gravity 

 1.830 (see D'Arcet). (Muspratt, 1879, vol. 6, 357.) This scale appears in Muspratt's Technische 

 Cheraie, 1879, vol. 6. 



(8) Bourgougnou. 66o=1.8427. This table is calculated according to the formula — 



p^ 144.3 

 144.3 -fZ 



in which P = density ; f?=degree Baume. This formula is obtained when Gay-Lussac's method is 

 used with sulphuric acid of specific gravity 1.8427 at 15° C. (Tucker, Manual of Sugar Analysis, 

 1881, pp. 108, 109.) Tbis scale appears in Proc. Am. Chem. Soc, vol. 1, No. 5, 1878; Tucker, 

 Manual of Sugar Analysis, 1881. 



(9) Bineau. 66o=1.8426. lu Bineau's tables, which Otto has calculated for 15° C. according 

 to Bineau's own statements, the specific gravity of the sulphuric acid (Schwefelsaiirehydrates) at 

 15° C. =1.8426. (Wagner, Jabresb., 1S69, vol. 15, 238.) This scale appears in Muspratt, 1879, 

 vol. 6, 358 ; Agendas Dunod, 1877 ; Lunge, 1879, vol. 1. 



(10) Yauquelin. 66^=1.842. The point 66° was obtained in sulphuric acid of specific gravity 

 1.830 (see D'Arcet). (Muspratt, 1879, vol. 6, 357.) Tbis scale appears in Ann. de Chimie et 

 Physique, 1 series, vol. 76; Bull. Ind. de Miilhouse, 1872; Muspratt, 1879, vol. 6, 359. 



(11) Morozeau. !!6C'= 1.842. Calculated by Morozeau by the formula 



'M'{v'-n) 



y- 



n'd' — n(l—x{d'—d) 



n, «', and ,r are the degrees of the instrument corresponding to the specific gravities, d, d', and y. 

 The 660=1.842 at 10° E. Tbis number is accejited because it corresponds to the highest specific 

 gravity of "acide sulfurique hydreux," because it is given by Theuard and because it seems gen- 

 erally accepted. In giving to ,r the values 1, 2, 3, up to 75, the corresjjonding values of y have 

 therefrom been deduced. (Journal de Pharmacie, Paris, 1830, vol. 16, p. 488.) Tbis scale appears 

 in Journal de Pharmacie, vol. 16, 488; Knapp, Chem. Technologic; ficole Centrale Lyonnaise. 



(12) Custom in France. 66o=1.842. Tbis table is based on Yauquelin's table. (Bull. Soc. 

 Ind. de Miilhouse (42) 1872, p. 211.) This scale appears in Bull. Soc. Ind. de Miilhouse, 1872. 



(13) J. Kolb. 660=1.842. 66o=pure sulphuric acid of specific gravity 1.842. (Lunge Soda 

 Industrie, 1879, vol. 1, 24.) This scale appears in Bull. Soc. Ind. de Miilhouse, 1872; Roscoe and 

 Scborlemmer, 1877; Wurtz, Diet, de Chimie, 1876; Lunge, Soda Industrie, 1879, vol. 1; Deut. 

 Chem. Kalendar, Dresden, 1877 ; Wagner, Chem. Tech., 1875 ; Muspratt, 1879, vol. 6, 359. Nos. 

 10, 11, 12, and 13 all give 66° Baume=1.842, though differing in other terms. 



(14) H. Pemberton. 66o=1.8354. Calculated by H. Pemberton in 1851, and adopted as stand- 

 ard by the Philadelphia College of Pharmacy the same year. This scale appears in U. S. Dispen- 

 satory, 12th, 13th, and 14tb editions. 



