34 Milk and Its Products. 
ous chemists, a+ considerable number of which give 
very accurate results. Chief among these methods 
for determining fat and total solids are the Babcock 
asbestos method and the Adams paper-coil method. 
In order that these determinations may be made 
with accuracy, balances of extreme delicacy, and 
apparatus more or less complicated and requiring 
considerable skill in its manipulation, are necessary, 
so that for ordinary commercial purposes they are 
practically out of reach. 
History of milk  tests.—Although consumers of 
milk had felt for a long time the necessity of 
some means of protection against dishonest dealers, 
it was not until the development of the factory sys- 
tem of manufacturing cheese (1850) and _ butter 
(1870) that some means of easily determining the 
composition of milk, particularly as to fat content, 
became important to both producers and manufac- 
turers. From that time on various methods have 
been devised, from the simple expedient of raising 
the cream in a small sample of milk in a graduated 
glass to apparatuses almost as complicated and 
difficult of manipulation as the gravimetric methods 
themselves. 
Cream gauges.—The simplest and one of the 
earliest methods used to determine the quality of 
milk is to set a small portion of it under such con- 
ditions that the cream would be thoroughly thrown 
to the surface and easily measured. These were 
known as cream glasses, cream gauges, or cream- 
ometers, and to a certain ex served ay i 
, t pogrtan oxtent. served a useful pur 
