APPARATUS AM) METHODS 241 



The microscope should have a one -inch and perhaps a two-inch 

 eye-piece and two objectives of say f- and -inch focal lengths. 

 By arranging the laboratory study of the pupils at differenl times 

 each microscope maybe used by three, four, or even more pupils. 



There should be a microtome or section -cutter for use by the 

 class. 



Bach pupil should have his own individual tools ami bottli 



reagents, as follows: 



1 good razor (hollow-ground on one side only), 

 1 small scalpel, 



1 pair forceps, 



2 sharp ueedles mounted in handles as penholders) (Fig. I 



1 medicine dropper, 



1 small camel's hair brush, 



A number of slide- and cover -glasses. 



< >f reagents, stain-, and other chemicals, there should be the 

 following: 



( rlycerine, 



Ninety-five per cent alcohol, 



Formalin (40 per cent formaldehydi 



irer (made of three parts turpentine and two parts m< 



crystals of carbolic acid I, 

 Canada balsam, 

 Ether, 



2 per cenl and 5 per cent collodion, 

 [odine dissolved in water, 



alcohol, 

 I [ematoxylin, 

 < topper sulfate solution, 



l it i 1 1 1 1 1 hydroxide boIuI i 



Pehling's solution (see paragraph '''*' 

 Alcanin (henna root in alcoho 



Tin- two per cenl collodion is made of forty nine part- alcohol, 

 forty-nine part- ether, two parts soluble cotton. Tin- th i-' 



suitable t<> use in Bticking sections to the slide to pr< 



their escape during the Btaining and clearing It need 



i. u-,,i mil'-- desired. Collodion is often useful for imbedd 

 material, as indicated under the lead "Imbedding" on p 

 Pupils must exercise neat care in using carbolic acid, a- it bti 

 the flesh. 



Hematoxylin -tain tnai be obtained ol dealers in a oumlil 



