THE MICROSCOPE. 



15 



injections exhibit under the ordinary Microscope a 

 mass of interlacing vessels, whose relation, being 

 all on the same plane, it is not easy to make out 

 with any degree of satisfaction. But placed under 

 the Binocular they at once assume their relative 

 position. Instead of a flat band of vessels, we now 

 see lnyer above layer of tissue ; deeper vessels an- 

 astomosing with those more superficial ; the larger 

 vessels sending branches, some forward and some 

 backward, and the whole injection assumes its 

 natural appearance, instead of being only like a 

 picture.^^ 



Fortunately for the possessors of the ordinary 

 Microsco})e the Binocular ar- 

 rangement can be readily ad- 

 apted to this instrument at a 

 cost of a few pounds. The 

 extra tube and eye-piece are 

 attached to the ordinary com- 

 pound body by a bayonet catch, 

 and can be removed therefrom 

 when not required; at the same 

 time the hole in the main body 

 being closed by a shutter, the 

 instruDient is reduced to its 

 original condition. The same 

 effect, however, is produced 

 without the removal of the 

 additional tube, by simply 

 withdrawing the prism that 

 bisects the light, which being 

 no longer divided passes up 

 the original tube as before. 



The accompanying diagram 

 (fig. 6) — a section of the Bin- 

 ocular — will give the reader a Fig. 6. Section of 

 correct notion of the mecha- Binocular Microscopa 



