INTRODUCTION 



nient. A glass graduate is almost indispen- 

 sable if accuracy in measuring fluids is de- 

 sired. (Fig. 1.) 



The chemicals needed are few in number 

 and small in quantity: Alcohols in varying 

 strength, which can be made by diluting a 95 





Fig. 1. 



per cent, alcohol, and keeping an absolute alco- 

 hol on hand. A few ounces of formaldehyde 

 will make enough solutions of different 

 strengths to be sufficient for the preparation 

 and keeping of many specimens. Of other 

 chemicals, such as xylol and cedar oil, only 

 small quantities are needed; enough to cover 



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