17 



best kind is that which contains three glasses in 

 one case, the focal distance of which are half 

 an inch, one inch, and two inches ; these three 

 glasses will, simple and combined, give seven 

 distinct powers. 



Setting Needle, (plate, figs. 20 and 21.) is 

 simply a needle fastened into a thin piece of 

 'wood about three inches long ; on the other end 

 of which a camel's hair pencil may be secured. 

 A pin curved towards the point, and fastened 

 into a piece of wood, will also be found use- 

 ful. These instruments are very useful for ex- 

 tending the wings and legs of insects ; and the 

 pencil for brushing off dirt, or extending the 

 limbs of those which are minute. 



Braces, (plate, figs. 2, 3, 5.) are merely tri- 

 angular slips of card used for confining the 

 wings, &c. They should be made of stout hot- 

 pressed writing pnper for delicate insects. 



Setting Boards are pieces of board covered 



c 3 



