Shs. 
Uranium Salts on Ferment Action. 263 
proteid matter of the saliva. Uranium is a well-known precipitant of 
albuminous matter and hence the larger the amount of albumin and 
globulin contained in the saliva, the weaker the retarding action of 
the uranium salt. Previous experiments have shown that saliva 
varies somewhat from day to day in its content of proteid matter, as 
well as in the amount of ferment, and although the former difficulty 
is obviated as much as possibie by diluting the saliva, still this point 
must be borne in mind in making comparisons of the different series 
of experiments. 
Uranyl acetate. 
This salt appeared somewhat more inhibitory in its action than the 
nitrate, due possibly to its greater acidity, The two following series 
show the extent of action: 
Total amount Relative 
U0.(C:H;02)2+H.O. reducing bodies. Starch converted. amylolytic action. 
0 0°4049 gram. 36°44 per cent. 100°0 
0-001 per cent. 02805 ‘ 20°74 56°9 
0-002 0:1698 15°28 41:9 
0-008 trace. 
0 04032 36°28 100-0 
0:00038 0:4831 38°97 107°3 
0-0005 03322 29°89 82:4 
0:0008 03192 28°89 79°6 
0:0010 0:2882 25°93 71:4 
The presence of 0:003 per cent. of the salt almost entirely stops the 
action of the ferment, while 0°0003 per cent. decidedly increases 
amylolytic action. ‘This latter influence is similar to that exerted by 
many other metallic salts in very small fractions of one per cent. and 
is doubtless to be attributed, in part at least, to the stimulating 
action of the acid-proteids formed, or in part, as suggested by 
Duggan,* to a more complete neutralization of the digestive fluid. 
Ammonio uranous sulphate. 
With this salt the following results were obtained: 
U(S04)2 +(NA4)o Total amount Relative 
SO, + H.0. reducing bodies. Starch converted. amylolytic action. 
0 0°3384 gram. 30°45 per cent. 100-0 
00003 0°3935 39°41 116°3 
0-0005 0-3798 34:18 112:2 
0-0008 0°3563 30°40 99°8 
0-001 0°3550 80°28 99-4 
0-002 i 0°2951 26°55 87-2 
0-003 0-0805 71°24 23°7 
*See Amer. Chem. Jour. vol. viii, p. 211. 
