NATURE OF DEPOSIT OBTAINED FROM MILK. 169 
Table IX. 
Solubility of Deposit and of Potential Ash in Water. 
Milk Total Total Soluble Ash of |Percent. of soluble 
a Deposit. Ash. Deposit. Sol. Dep. Deposit|Pot. Ash 
29 |0-3443 gm. 0-0297 gm.|0-1019 gm-/0:0268 gm.| 34:7 | 90:3 
36 |\0-2070 ,, 0-0180 ,, |0-0985 ,, (0:0095 ,, | 47-5 | 52°8 
37 |0-1084 ,, |(0-0107 ,, 10-0697 ,, [0:0087 ,, | 64:2 | 88-8 
38 |0:1286 ,, |0-0122 ,, 00318 ,, |0-:0087 ,, | 24:7 | 71:3 
39 |0-1339 ,, (0-0120 ,, 0:0936 ,, (0-0111 ,, | 69°9 | 92-4 
By the term “potential ash’’ is meant that portion of 
the deposit which after ignition forms the actual ash. The 
term is used to avoid speaking of the inorganic matter of 
the deposit, as it is uncertain what portion of the substances 
which go to form the ash is originally in an organic form 
of combination; part of the phosphorus and calcium for 
example, is probably present in the deposit in an organic 
compound (calcium caseinogenate). 
The amount of the total deposit which goes into solution 
is seen to be very variable, ranging from 24°7 to 69°9%. 
The fraction of the potential ash which dissolves is greater 
still and varies from 52°8 to 92°4°%. The solubility of the 
potential ash of the deposit is in marked contrast to that 
of the actual ash. 
In the case of milk 29 the following figures were obtained: 
Total Ash. | Soluble Potential Ash.| Soluble Actual Ash. 
0-0297 00268 (903%) | 00055 (185%) 
The nature of the combinations of the elements which 
go to form the ash is therefore completely changed by 
ignition. The fact that part of this deposit from milk is 
soluble in water is interesting as it shows that in addition 
to the presence in milk of substances or conditions which 
keep insoluble materials in a state of fine suspension and 
prevent their precipitation, there are also present sub- 
stances or conditions which keep soluble matter in a similar 
state. 
