8 .CHAPTER I. 



much better controlled, and many excellent stains can in this way be em- 

 ployed that are not available for staining in bulk ; and of course sections 

 can be stained much more rapidly than material in bulk. But many 

 workers consider that staining in bulk is frequently more convenient, and 

 therefore preferable so long as the demonstration of minute detail is not an 

 object. 



The most convenient vessels, I find, in which to perform the various 

 operations of staining, differentiating, dehydrating, clearing, etc., on the 

 slide, are flat-bottomed corked glass tubes. I have mine made 10 centi- 

 metres high and 27 millimetres internal diameter. Each of these will then 

 take two slides, English size, placed back to back. To make a stand for 

 them, take a piece of deal board, 3 centimetres thick, and with a centrebit 

 bore in it series of holes about 15 millimetres deep and of the diameter of 

 the tubes, and about 3 centimetres apart lengthways and 1| crossways. A 

 board of 15 centimetres width and 45 length will take twenty-one tubes in 

 three rows of seven each in the holes ; and others may be stood up between 

 the rows without much risk of their falling. 



6. Resume of the Section Method. It was stated in the first 

 edition of tlds work that l< the great majority of preparations 

 are made by fixing either with sublimate or a picric acid com- 

 bination, washing out with alcohol, staining with alcoholic 

 borax-carmine, imbedding in chloroform paraffin, cutting 

 with a sliding microtome, and mounting the sections in series 

 in Canada balsam." But histological practice has greatly 

 changed since then, and I would now suggest the following 

 as giving in very many cases greatly superior results : Fix 

 in such one of the fixing agents recommended in later 

 chapters as may be most suitable to the case ; wash out ; 

 dehydrate ; clear with oil of cedar- wood ; imbed in paraffin ; 

 mount sections on the slide by the water method or with 

 Mayer's albumen medium; stain as desired, and mount in 

 balsam or damar. That, or something like that, is now the 

 practice of many of the most advanced workers ; but the 

 beginner will perhaps do well to commence by the simpler 

 procedure first recommended, which is very suitable for 

 obtaining rapidly a general view of the forms and relations 

 of anatomical elements. 



7. Preparation of Entire Objects, or of Material that is not to 

 be sectioned. The treatment of objects which can be studied 

 without being cut into sections is identical with that above 

 described, with the omission of those passages that relate to 

 imbedding processes. Its normal course may be described 



