64 THOMPSON YATES LABORATORIES REPORT 
2. — Digestion, of Starch. 
Strength of 
formalin. 
Retarding action on 
Zymine. 
Pancreatine. 
Liquid Taka- 
diastase. 
I in 100,000 
I „ 50,000 
I „ 10,000 
3.6 per cent. 
8.2 
8.5 „ 
13.0 per cent. 
16.0 
16.7 „ 
5.0 per cent. 
8.5 » 
18.0 
B. — Proteolytic Digestion 
1. — Pepsin Digestion of Raw Beefsteak. 
Strength. 
Retarding Action. 
I in 50,000 
I „ 100,000, after 24. hours' previous contact. 
I „ 50,000 „ „ 
I ,, 10,000 „ „ 
2.6 per cent. 
8.6 
8.7 » 
12.6 
2. — Pancreatic Digestion : Digestion of Casein. 
Strength. 
Retarding Action. 
1 in 50,000 
I „ 100,000, after 20 hours' previous contact ) 
with preservative. ) 
I ,, 50,000 „ „ „ 
I „ 10,000 „ „ „ 
0.3 per cent. 
54 
5-9 
8.6 
Thus formaldehyde, in strengths of from i in 50,000 to i in 10,000, appears to have a 
deleterious effect on the digestive ferments to an extent varying from 0.2 per cent, up to 18 per 
cent., so that it is possible that the total effect of formalin, after acting on the different digestive 
ferments on its w^ay through the alimentary tract, might amount to a very considerable total. 
RiDEAL and Foulerton,* from experiments to ascertain the 'preserving' effect of formalin on 
milk from a bacteriological point of view, decided that not less than i part in 50,000 is necessary 
to preserve milk for 48 hours. There is but little doubt that milk, after passing through the hands 
of tlie wholesale purveyor, dairyman, and milkman, often contains considerably more than this 
quantity. 
* hoc, cit. 
