160 



Canadian Record of Science. 



When the residue left by evaporation of milk is burnt at a 

 low red heat, the inorganic constituents of the milk remain 

 behind as ash. The quantity of ash contained in cow's milk 

 usually amounts to about • l 7 per cent. 



MEAN COMPOSITION OF THE ASH OF COW'S MILK. 



(Schrodt and Hansen.) 



Potassium Oxide 25-98 



Sodium Oxide 10" 75 



Calcium Oxide 20"87 



Magnesium Oxide 2 • 76 



Iron Oxide "13 



Sulphuric Anhydride 3-99 



Phosphoric Anhydride 23-63 



Chlorine 15-08 



The following Table compiled from various sources will 

 enable us to compare the milk of different animals: — 



ANALYSIS OF THE MILK OF DIFFERENT ANIMALS. 



Water. Solids. Fat. 



Human Milk 87 



Cow 87 



Sheep 7S 



Buffalo 81 



Goat 86 



Camel 86 



Mare 90 



Ass 90 



Sow 82 



Hippopotamus 91 



Bitch 76 



Cat SI 



Porpoise 41 



12-2 



12-5 



21-3 



18-3 



13-6 



13-1 



9-9 



9.5 



17-6 



9-0 



23-4 



18-4 



58-9 



Albu- 

 min- 

 oids. 

 2-5 

 4-0 

 6-3 

 4-0 

 4-5 

 3-8 



Sugar. Salts. 



4-4 

 9-9 



5-5 



4-0 

 5-1 



4-5 

 4-0 

 5-7 

 6-6 

 5-7 

 4-0 



3-2 

 4-9 

 1-3 



In order to form a judgment of the value of milk as a food, 

 a few words as to the composition of the various substances 

 which constitute the food of man and animals will be 

 useful. 



Nutritive substances may be classed as follows : — 



1. Albuminoids. 



2. Fats. 



3. Carbohydrates. 



