CHOICE AND USE OF APPARATUS 



off square at the other; at about its centre it is 

 much wider than at the top or bottom. It is a 

 most useful piece of apparatus for picking up small 

 water animals which we wish to examine. By 

 putting the pointed end of the pipette just over an 

 Amoeba, for example, and sucking gently at the 

 other end, we shall draw some water and the 

 animal into the swollen part of the tube. If we 

 then place one finger over the end of the pipette 

 to which we have applied suction we can transfer 

 the contents wherever we wish without it running 

 out, as soon as we remove our finger the pipette 

 empties itself. The dissecting knives are useful for 

 cutting up specimens before examination, the 

 mounted needles for teasing them, that is to say 

 tearing them into fine shreds. The brushes we may 

 use instead of the pipette, for picking up small 

 objects from water, or when dry. The watch 

 glasses are useful for examining objects such as 

 sponges, water fleas, etc., under water. They are 

 just as satisfactory for most purposes as the speci- 

 ally constructed zoophyte troughs and, of course, 

 very much cheaper. The razor is required for section 

 cutting concerning which we will say a few words. 

 For section cutting, special razors are sold, they 

 iare heavy as a rule and not hollow ground. Many 

 imicroscopists aver that good sections cannot be cut 

 with a hollow ground razor, we beg to differ, how- 

 ever. On this point we would advise our readers 

 to select whichever pattern suits them best; there 

 is no need to buy an expensive razor, for our early 



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