and Toxic Agents on the Amylolytic Action of Saliva. 79 
be the effect on the amylolytic action of the ferment? Might we not 
expect, knowing that albumin and mercuric chloride readily combine, 
that the proteid matter present in the saliva, would serve as a shield 
to protect the ferment from the action of the mercury or other similar 
metallic salt? At the same time it might be supposed that, the fer- 
ment being left intact, any mercury-albumin compound formed might 
retard or destroy the ferment, though less energetically than the 
metallic salt alone. 
In an attempt to throw some light upon these points the following 
experiments were tried: 
Action of mercuric chloride in the presence of larger amounts of 
Jerment and proteid matter. 
a. with 10 e.¢. of original saliva. 
HegClo. Wt. Cu in 4. solani bodies: éconorted. 
0 0-1772 gram. 0°3624 gram. 32°61 per cent. 
0°0005 per cent. 071735 0°3548 31°93 
0°0010 01695 0°3464 31°16 
b. with 5 c. ec. of original saliva. 
0 071720 gram. 0°3516 gram. 31°64 per cent. 
0°0005 per cent. 01340 0°2728 24°55 
Comparing these results with those previously obtained with the 
same percentages of mercuric chloride, but with 2 c.c. of original 
saliva, we have: 
HegClo. 2¢.¢. Saliva. 5c. c. Saliva, 10 ¢.c. saliva. 
0 44°28 per cent. 31°64 per cent. 32°61 per cent. 
9:0005 per cent. 23°40 24°55 31°93 
0-001 16°92 has oe 31°16 
The intensity of action of the mercuric chloride, say 0°0005 per 
cent. in the three cases, varies greatly; thus with 2 c.c. of saliva the 
difference in the percentage of starch converted, between the control 
and the 0°0005 per cent. is 20°88, while with 5 ¢.c. of saliva the differ- 
ence is 7°09 and with 10 c.c. of saliva only 0°68. Obviously then, the 
action of a given percentage of mercuric chloride can be considered 
as constant only for a given mixture or under definite conditions. 
Moreover, it would appear (in the 10 ¢.c.) that either the albuminous 
matter of the saliva has combined with all of the mercury, leaving 
the ferment free to act in a normal manner, except so far as it is 
impeded by the mercury-albumin compound, or else that only a small 
proportion of the ferment has been chemically precipitated, leaving an 
amount sufficient for energetic amylolytic action, since, as is well 
