LXI. "me microscopic technique of haematology. a. 

 Spreading blood, b. Fixing and staining. 



a. "Making the spread.'* 



1. Appliances. Microscope with one-seventh objective; 

 needle and holder; square cover glass, J inch. 



2. Preparation. Clean six or more cover glasses with di- 

 lute acetic acid, soap and water, and alcohol. 



3. Operation. Puncture the ear and obtain blood as de- 

 scribed in Lesson LV. Hold a cover glass in each hand 



FIG. 45. 

 FIG. 45. Showing the way to hold the cover glasses. 



as shown in Fig. 45. With the one held in the left hand 

 just touch the center to the bottom of the drop, as in 

 Fig. 46, being careful not to touch the ear. Quickly 

 place upon it the cover glass held in the right hand as 

 in Fig. 47. If the blood is fresh and the glasses clean, 

 it will spread rapidly and evenly by capillary attraction. 

 The instant it stops spreading seize the upper cover 

 glass with the right hand as shown in Fig. 48, and pull 

 it quickly apart horizontally. lace the cover glasses, 



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