THE STRUCTURE OF 



spot should be selected near a window, out of the 

 direct light of the sun, in which to place a small, 

 , steady table. On this the Microscope should 

 be placed, and the object- 

 glass should be screwed on 

 to the tube. The mirror 

 should be then adjusted so 

 us to throw a bright ray of 

 light on to the object-glass. 

 The eye-piece having been 

 previously placed at the top 

 of the tube, the Microscope 

 is now ready to receive a 

 transparent object. If the 

 object to be examined is an 

 animalcule, it may be con- 

 veyed to the animalcule- cage 

 by means of a glass tube, 

 called a pipette or dipping- 

 tube (fig. 12), which should 

 be dipped into the water 

 where the object is con- 

 tained, with the finger 

 covered over the upper ori- 

 fice, so that no air can escape. 

 By taking the finger off 

 when the tube is in the 

 water, the fluid will rush 

 into the tube, and with it 

 the object to be examined. 

 The finger is again applied 



m u to the to P f" the tube, and 

 Tubes. , n i v i 



the fluid obtained conveyed 



to the animalcule- cage. Only such a quantity of 

 the water should be allowed to fall out of the tube 

 on to the cage as will enable the observer to put 



. 10 TV 

 Fig. 12. Dipping 



