Journal of Applied Microscopy. 



297 



APPARATUS. 



The following list of apparatus includes a fair equipment for histological 

 work : a microscope magnifying at least 400 diameters ; a hand microtome ; 

 a sliding microtome ; a razor ; a paraffine bath and lamp ; a turn-table ; a scalpel ; 

 a pair of needles ; pair of scissors ; pair of forceps ; stender dishes ; minots or 

 watch glasses ; a wash bottle ; a graduate (50 or 100 cc.) ; pipettes ; slides, 1x8 

 inches; round covers, IS mm. or ^ inch in diameter; and square covers, //g 

 inch. 



The hand microtome will be found extremely 

 useful, especially by the busy teacher who has large 

 classes. Any sliding microtome, if kept in good 

 order, will be sufficient for the work to be described 

 in these papers, but those of medium size are to 

 be preferred. 



The stout razors our grandfathers used to shave 

 with are excellent for free-hand sectioning, for hand 



microtome work, and even for cutting paraffine sections on the sliding 

 microtome. The blade should be flat on one side (Fig. 1 A). Modern razors 

 (Fig. 1 B) with delicate blades, though good to shave with, are worthless for 

 cutting sections of plants. The razor is a necessity ; if a microtome knife is 

 wanted in addition, it should have a bevel about like Fig. 1 A. A short blade, 

 three or four inches long, is to be preferred to the longer ones, which are 

 much more troublesome to sharpen. 



There are numerous forms 

 of the paraffine bath. Those 

 with a water-jacket, thermo- 

 meter, and a thermostat, to 

 maintain an even tempera- 

 ture, are the most convenient 

 where gas is available. As a 

 rule it is easier to keep the 

 temperature constant in the 

 larger baths. A bath which, 

 if carefully watched, gives the 

 very best results, can be 

 made by any tinner, and is 

 very inexpensive. The ac- 

 companying figures show the 

 form and dimensions. 



It is made of copper one 



thirty-second of an inch thick, 



but thicker copper is as good 



or better. There should be two boxes to contain the paraffine ; the covers to 



the boxes should fit loosely. Any kind of a lamp may be used. 



Stender dishes are now very generally used for staining on the slide. The 

 form shown in Fig. o A is made just large enough to hold two slides, placed 



A, top view ; B, side view 

 contain the parattine. 



C, end view ; D, box to 



