THE ESSENTIALS OF HISTOLOGY. 



LESSON V. 



THE AMCEBOID PHENOMENA OF THE COLOURLESS 

 BLOOD-CO RP USCLES. 



1. MAKE a preparation of blood from the finger in the usual way. Draw 

 a brush just moistened with oil around the edge of the cover-glass to check 

 evaporation. Place the preparation upon a ' warm stage/ and heat this to 

 about the temperature of the body (38 C). Bring a white corpuscle under 

 observation with the high power, and watch the changes of shape which it 

 undergoes. To become convinced of these alterations in form, make a series 

 of outline sketches of the same corpuscle at intervals of a minute. 



The simplest form of ' warm stage ' is a copper plate of about the size of 

 an ordinary slide, perforated in the centre and with a long tongue of the same 





FIG. 18. SIMPLE WARMING APPARATUS, COMPLETE, SHOWN IN OPERATION. 



metal projecting from the middle of one edge (fig. 18). The copper plate 

 rests upon the stage of the microscope with a piece of cloth or other non- 

 conducting material between. The preparation is made upon an ordinary 

 slide, which is placed upon the warm stage and pressed into contact with 



