82 LABORATORY BACTERIOLOGY 



In making these preparations from blood, hold a cover glass 

 by the edge with a pair of dissecting forceps. With the plati- 

 num loop place a drop of blood on the cover glass near the 

 forceps. Take a thick, square cover glass by the edge, rest it 

 on the first above the drop of blood, hold it at an angle of 

 about 20 from it, and draw it down over the first, thus spread- 

 ing the blood in a very thin, even film over the surface. If 

 the film is thick, the preparation should be rejected and 

 another made. 



