kh. H. Lee—Atomie Weights of Cobalt and Nickel: 49 
In my first series of experiments I employed only the cobalti- 
cyanides of brucine and strychnine, the corresponding salts of 
morphine, narcotine, chinine and cinchonine having been found 
difficult to prepare in a state of purity by recrystallization. 
The brucine and strychnine salts were prepared by decompos- 
ing the sulphates of these bases with cobalti-cyanide of barium, 
and repeatedly recrystallizing the salts formed. The brucine 
salt crystallized in beautiful white, barb-shaped crystals with a 
high luster. It was but slightly soluble in cold water, and erys- 
tallized with remarkable facility. The strychnine salt was in 
beautiful, nearly colorless needles, and like the brucine salt erys- 
tallized almost completely from its solution on cooling. Six 
analyses: were made with each of these salts. 
Of the strychnine salt— 
0°7084 gr. dried at 115°C. lost 0°0392 gr. of water = 5°53 p. c. 
The formula, €o,Cy , (Cy, H,2N202),H,+80H2, 
requires 557 p. ec. water of crystallization. : 
he following are the results of my determinations of the 
amount of cobalt in this salt: 
No. Salt taken. Cobalt. Cobalt, p.c. At. weight. 
i& 0°4255 or. 0°0195 gr, 4°583 59°22 
0°4025 “ 0°0185 “ 4°596 59°36 
3 0°3733. “ 0°0170 “ 4°554 58°83 
4 0°4535 “ 0°6207 “ 4°564 58°96 
5 0°2753 “ 0°0126 “ 4°57 59°14 
6 071429 “ 00065 “ 4°549 58°76 
Mean, 4°5705 59°05 
The probable error of the mean is +-0-012, and the atomic 
weight of cobalt 59-05, with a probable error of +156. In the 
- case of the brucine salt, three determinations of the water of 
crystallization were made. 
0°4097 gr. gave 0°0465 gr. water at 117°C. = 1135 p.e 
0°3951 gr. “ 0°0453 gr, “ - 110° C, 2. 20s6 p. 6. 
06653 or, “ 00752 gr. “198° GC. Se 1400 pp. «. 
The mean of these three determinations is 11:37 p. ¢. 
The formula €0,Cy , o(Cs3H2_.N20,)¢He+200H, 
os igs 11°39 p. c. water of crystallization. 
€ results of my determinations of the amount of metal in 
this salt are as follows: 
t taken. Cobalt. Cobalt, p.c. At. weight. 
I, 0°4097 gr. 0°0154 gr. 3°759 “41 
2. 03951 “ 00147 “ 3°720 58°76 
3. 0°5456 * 00204 3°739 59°08 
4, 0°4402 “ 070165 “ 3°748 59°22 
5 0°4644 * 0°0174 “ 3°747 59°21 
6 04027 * 00151 “ 59°24 
74 
Mean, 3°7437 59°15 
Am. Jour. Sct —Tuirp Serres, Vor. II, No. %.—JuLy, 1871. 
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