General Instructions 13 



g. In the following directions, when reference is made to 

 another method, the Roman numerals refer to the number of the 

 method, the capital letters refer to the formulae, and the Arabic 

 numerals and small letters refer to the paragraphs and divisions 

 of paragraphs given in that method. Where no Roman numerals 

 are cited, the references have to do with the method in which 

 they occur. The page containing the detail referred to is also 

 given. 



10. Method I. is given in fuller detail and with more explana- 

 tory notes than any of the methods succeeding it. The student 

 is advised to read it over before undertaking any of the methods 

 involving imbedding and sectioning in paraffin. 



11. Before undertaking any method, read the directions 

 over carefully, paying special attention to the tirne it will take 

 to complete it, and more particularly to the distribution of that 

 time, so that plans may be laid accordingly. Often a series of 

 steps, once started, must be followed without interruption, and 

 much inconvenience may be saved by taking the precaution to 

 know beforehand the time required between two stages at which 

 the procedure may rest. It is also advised that the necessary 

 reagents and vessels be prepared before beginning a method. 



Since it is impossible to give rules which will cover all cases, 

 a wide margin is provided, upon which the student may make 

 note of such exceptions or improvements as his experience may 

 suggest. 



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