86 Proceedings of Royal Society of Edinburgh. [sess. 
an open flocculent precipitate ; the first and third showed no 
change. 
After eight days I tested the tubes for caseoses or peptones by 
the Biuret reaction. The pancreatic digestion yielded the test 
most frankly, next thereafter that with liquor pepticus, then that 
with HC1 and pepsine, then that with pepsine alone (probably due 
to bacterial fermentation of caseinogen), and lastly a mere trace 
with the glycerine-extract. 
My experiments with milk mixed with water or with CaH 2 0 2 , 
in order to render it more digestible, as it is alleged, tend to show 
that this property is entirely due to the greater laxity of the clot 
which forms when the solid particles of milk are, from any cause, 
separated from one another. Evidently the power of rennin for 
binding particle to particle is weakened when it has to act through 
a greater distance upon these particles : none of these clots in 
diluted milk has the absolute laxity of the pancreatic clot in milk. 
Milk heated to 100° C. for 40 Minutes as a Method of 
INCREASING ITS DIGESTIBILITY. 
This I fully confirm. Sir William Priestley * called attention 
to Mons. Budin of Paris’s observation that milk, not diluted and 
not boiled, but merely treated as above, yields a clot of digestibility 
superior to that produced in previously unheated milk. 
I find the clot with Benger’s liquor pepticus is, in the case of 
the heated milk, an exquisite jelly of great friability upon any 
such agitation as occurs with the gastric movements, whereas the 
tenacity and density of the clot by pepticus in ordinary milk would 
make the mass resist this breaking process for a much longer time. 
After some hours there was distinctly more proteose in the tube 
with the soft clot than in that with the hard. 
On Boiled Milk. 
The “ scum ” which forms on this is merely a surface dessication 
of caseinogen with possibly some lact. -album in. 
Milk boils at 104'5° C. I have corroborated the statement that 
* Brit. Med. Jour, for 7tli Bee. 1895. 
