Compounds of Albumin and Myosin. 307 
Harnack states* that he was able to obtain the copper albuminate 
quite free from ash by dissolving the freshly precipitated albuminate, 
after it had been thoroughly washed, in sodium carbonate, filtering 
and reprecipitating the compound by careful addition of acid. By 
repeating this process several times the adhering inorganic matter 
was entirely removed. It seemed questionable, however, whether 
this treatment might not induce some alteration in the compound. 
The two following series of experiments were tried with the inten- 
tion of throwing some light upon this point. 
Series VI. 
With CuSO, | 
No. Am’t sub. taken. Wt. CuO. Per cent. Cu. Wt. Cu.s. Per cent. Cu. 
la 0°6320 gram. 0:0091 gram. 1°15 0:0080 gram. 0:99 
b 0-6980 0:0099 1:13 0-0086 0:98 
2a 05428 0:0077 1:12 0-0070 1-01 
b 05121 - 00077 1:19 0-0061 0-95 
3 0°3146 00080 2°03 0-0068 acral 
With Cu(C,H,O,).. 
4a 0°6105 00085 are 0-0075 0-96 
b 05836 0:0078 1:06 0-0072 0:99 
5a 05996 00087 1°15 00081 1:06 
b 05592 00082 1:16 0-0069 0:99 
6 0:4139 0-0131 2°51 0-0115 2.19 
In this series of experiments all of the preparations, as before, were 
made from the purified albumin. Nos. 1, 2, 4 and 5 were, after pre- 
cipitation, simply washed with water until the washings gave no reac- 
tion either for copper or albumin. No. 3, after being washed in a 
similar manner, was dissolved in very dilute sodium carbonate and re- 
precipitated by neutralization with dilute hydrochloric acid. No. 6 
was dissolved up twice in this manner and both preparations were 
finally washed free from chlorine. A glance at the analyses shows 
plainly that this treatment has tended to increase the percentage 
amount of copper in the albuminate; due, doubtless, either to with- 
drawal of a portion of the albumin by the sodium carbonate, or else 
to a partial dissociation of the eee by the long continued wash- 
ing with water. 
The first reprecipitation has apparently increased the amount of 
copper in the compound fully 0°7 per cent., the second reprecipita- 
tion 0°5 per cent. more. 
* Loe. cit., p. 202. 
