STUDY OF ANIMAL LIFE 



23 



Notes for a Lesson on the Cow. (Cont.) 



Facts to be " drawn out" of chil- 

 dren by direct and indirect ques- 

 tions (educere, to draw out). 



Methods of teaching; specimens, 

 drawings, experiments, &c. 



5. Composition of Milk. 

 Milk is a liquid containing : 



1. Fat (in suspension). 



2. Albumen (in solution). 



3. Sugar 



4. Mineral matter 



5. Composition of Milk. 



Articles Required. 

 Milk. 



Two glasses. 

 Butter. 



Cloth strainer. 

 Cheese. 



Enamel evaporating dish. 

 Limejuice. 



1. Fat. (a) Let children ex- 

 amine. Hold a glass of milk to 

 the light, and observe the fat 

 globules. 



(6) Show children a glass of 

 milk that has been standing for 

 some hours, and let them point 

 out that the fat has risen to the 

 surface. 



2. Albumen. Pour some lime- 

 juice into a glass of milk, and 

 observe that it curdles. The 

 solid matter, consisting of albu- 

 men, is known as curd, while 

 the liquid left is whey. 



3. Sugar. Separate the curd 

 and the whey by straining 

 through a cloth. The liquid 

 which goes through contains 

 sugar and mineral matter. 



4. Mineral Matter. Evapo- 

 rate the solution in an enamel 

 dish over a fire. It will be 

 noticed that the residue left after 

 the liquid passes off will soon 

 begin to darken in colour. This 

 is the sugar burning. Continue 

 heating until only the mineral 

 matter is left behind in the 

 form of ash. 



