316 Chittenden and W hitehouse— Metallic 
(d) Zine Compounds. 
With zinc we made but a few experiments and those mainly to see 
whether the low percentage of iron found in the iron albuminate 
would be substantiated by a corresponding percentage of zinc in the 
zine albuminate. Lieberkiihn has prepared and analyzed a zine 
albuminate, made by the action of zine sulphate on a neutral solu- 
tion of alkali albuminate, and he found the compound to contain 4°66 
per cent. of zine oxide. 
Our preparations were made by the action of a similar zine salt on 
a solution of purified and dialyzed albumin. Following are the 
results obtained with two preparations made from two distinct lots 
of albumin : 
No. Amt. sub. taken. Wt. ZnO. ‘Per cent. ZnO. Per cent. Zn. 
la 0:2424 gram. 0:0031 gram. 1°27 0-98 
b 0:2833 0:0034 1:21 0:97 
2a 02166 0-0023 1:06 0:83 
b 0°2354 0:0025 1:08 0:86 
The average of these two results shows a composition proportional 
-to that found in the case of the iron albuminate and suggests plainly 
that if we have to deal in these cases with a single albuminate of 
constant composition, the percentage amount of metal is much 
smaller than formerly was supposed. 
Further, the percentage of zinc found accords closely with the 
theoretical amount for a zinc albuminate formed on the type of the 
copper compound. 
(C; BGaNG “SOn2). + Zn—H.=0°99 per cent. Zn. 
(e) Uranium Compounds. 
N. Kowalewsky* has recently called attention to the use of uranic 
or uranyl! acetate as a reagent for albuminous matter, and. has shown 
that it is not only a good precipitant of albumin at ordinary temper- 
atures, but also that it is an extremely delicate one. Further, 
Kowalewsky states that the uranyl-albumin compound on ignition 
leaves a dark, olive green ash, composed of the green uranoso-uranic 
oxide, U,O,. A determination of the amount of this ash in several 
preparations showed 12°09 to 13-4 per cent., presumably of U,O,. 
* Essigsaures Uranoxyd, ein Reagens auf Albuminstoffe. Zeitschrift fir Analy- 
tische Chemie, 1885, p. 551. 
a 
