V. 



ANALYSIS OF MILK. 



1. Determination of the Amount of Water. Place 5 or 

 10 cc. of milk in a weighed dish, preferably a platinum dish, 

 evaporate to dryness on the water-bath, heat to constant 

 weight at 105, and weigh. 



If the greatest possible accuracy is desired, the milk must 

 be weighed, not measured, and the dry residue must also be 

 protected from the air in order that it may not take up water 

 during the weighing. This applies to all similar determina- 

 tions. Both these objects may be attained by using a plati- 

 num crucible for the determination. This is placed in a 

 large weighing-glass, the glass is then closed and the weight 

 of the whole determined. Five to ten cubic centimeters of 

 the milk are then introduced into the crucible, the weighing- 

 glass is closed, and the quantity of the milk is determined by 

 weighing again. The crucible containing the dry residue is 

 also weighed in the weighing-glass. 



2. Determination of the Amount of Ash. The dry resi- 

 due is carefully carbonized, then more strongly heated, but 

 not ignited at too high a heat, until the carbon is completely 

 burned. If complete combustion cannot be attained in this 

 way, extract the half-burned residue by cautiously warming 

 with water, filter through an ashless filter, etc., as described 

 under "Faeces" and "Meat." 



3. Determination of Fat. (a) Let 5 to 10 cc. of milk 



drop on kaolin or burnt gypsum or sand, contained in the 



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