102 NATURE STUDY BY GRADES 



Experiment. Try to twist a few hairs into a thread ; 

 twist a few fibers of wool into a thread ; note the difference 

 in results. Examine hair and wool with a microscope, and 

 account for the above results from the difference in structure. 



LESSON XXV 

 THE MANUFACTURE OF WOOL 



Bring some wool to school, and let the pupils take part 

 in as many of the processes of manufacture as possible. 



What is the first thing to do with the wool? The pupils 

 may wash the samples, and the teacher explain how large 



A SHUTTLE AND SIMPLE LOOM 



quantities are washed in great kettles heated by steam. It 

 is then dried, most of the water being driven off by whirling 

 it rapidly in a machine made for that purpose. 



When the wool is dry, what is usually the next process? 

 How is wool dyed? If convenient, a small sample may be 

 colored with prepared dyes, though vegetable dyes, collected 

 by the pupils, would be better. 



How may the matted masses of wool be broken up so as 

 to be spun? Describe a wool-picking machine, and show 

 how it tears the wool into a fine, feathery condition. Were 

 it possible, the children should visit a woolen mill and see the 

 machinery at work. At least, pictures of the processes should 

 be used. 



