STAINING OF PREPARATIONS 



53 



contact with the hot iron of the bottom or sides of the steriliser. Funnels, 

 conical glasses, and other glass apparatus of small size can be kept sterile by 

 treating in a similar manner. 



The Making and Staining of Preparations for the 



Microscope 



General note- 

 It will be found convenient to stain on the glass slide rather 

 than on the cover glass, which should be kept for its legitimate 

 purpose. The slides are easier to clean and handle, are less 

 liable to breakage, and the result is the same. If it is desired 

 to keep the preparation as a permanent cabinet specimen a cover 

 glass may be applied with Canada balsam in exactly the same 

 manner as in the case of sections, 

 but under ordinary circumstances 

 this will be found unnecessar}'. 

 Microscopic examination of the 

 preparation can be made as soon 

 as the film has dried after staining, 

 by placing a drop of cedar-wood 

 oil directly upon the stained 

 surface and bringing the lens 

 of the microscope down upon it 

 without the intervention of a 

 cover glass. If it is desired to 

 preserve the specimen, either for 

 further examination, or for mount- 

 ing, the oil is easily removed with 



the aid of a little xylol or benzole applied with a camel's hair 

 brush. With a due amount of care there is but little chance of 

 removing any of the stained film in so doing. It will be found 

 convenient to have upon the working bench a small wide mouth 

 specimen jar accurately stoppered, and containing sufficient waste 

 xylol or benzole for the purpose. The method of removing the oil 

 is shown on Fig. 5. 



Cleaning" slides and cover glasses— 



Slides. — Slides which have been already used should be allowed 

 to soak for some days in a strong solution of Hudson's or other 

 extract of soap in hot water, care being taken that they do not 

 cling together surface to surface. All traces of the film or stain 

 should then be carefully removed with a pad of cotton-wool dipped 



Fig. 5. 



