18 LABORATORY METHODS OF 



4. Regulate the thickness of the tissue by the use of 

 the milled head on the under surface of the microtome. 

 (B. & L. is the best for students' use.) 



Exercise No. 4. Use the Centrifuge. 



1. Attach the instrument to the table and place the 

 tubes in place. 



2. Revolve the tubes moderately for three minutes. 



3. Take the sediment out and examine with the mi- 

 croscope. 



The Haematokrit is used in the same way, only re- 

 volved more rapidly. 



Exercise No. 5. Make a spread of yeast-plant. 



1. Obtain some yeast and place it in a little water in 

 a test tube ; set aside in a warm place for a short while. 



2. Take a pipette and compress the bulb so as to get 

 some of the yeast and water in the pipette. 



3. Now place a small drop of this material on the 

 slide and examine. 



4. Examine with H. P. (1-6 in. Obj.) 



5. Observe the morphology, grouping, budding and 

 search for a chain. 



6. Make drawings and note all you see. 



This lesson is to illustrate the mode of reproduction 

 of cells, morphology (or shape), the contents of cells, 



