224 THE MICEOSCOPE. 



sesses the property of coagulating albumen, and there- 

 fore cannot be used iii the preservation of ova, cellular 

 tissue, the white corpuscles of the blood, &c. 



Goadby's method of preparing -marine-glue for 

 cementing cells is as follows : dissolve separately equal 

 parts of shell-lac and india-rubber in coal or mineral 

 naphtha, and afterwards mix the solutions carefully by 

 the application cf heat. It may be rendered thinner 

 by the addition of more naphtha, and redissolved, 

 when hard or dry, by adding naphtha, ether, or liquid 

 potash. 



Multiple Sfaining, Animal and Vegetable. 



"Within a short period of time the staining of 

 animal and vegetable tissues for microscopical exami- 

 nation may be said to have almost superseded injec- 

 tions. The results obtained lent a charm to the stain- 

 ing process, and it was soon seen that other and far 

 more important advantages could be gained by its 

 adoption and further development. Formative tissue 

 and structural differences, heretofore difficult to differ- 

 entiate, were by a method of double staining, that is 

 dying the tissues of two or more colours, made instruc- 

 tive and palpable even by the aid of only moderate 

 powers of the microscope. 



Various methods, mostly differing in details, have 

 "been from time to time proposed for the combi- 

 nation of colours and producing striking and perma- 

 nent results. One of the most useful manuals of 

 reference on the subject is Dr. Thin's, 1 whose experi- 

 ence is founded on methods adopted by continental 

 schools, and that of Ranvier's in particular. The 

 student is recommended to provide himself for ordinary 

 histological work, and which he should as far as possible 

 become proficient in before he can expect to succeed in 

 staining and preparing tissues, the following instru- 

 ments : Two needles fixed in handles ; strong and fine 

 scissors ; a scalpel ; a razor ; flat 011 the under surface 

 and slightly grooved on the upper ; a section-lifter or 



(1) An Introduction to Practical Histology, by George Thin, M.D. Bail 

 Iftre, Tindall <fe Cox, King William Street, Strand. 



