152 CHAPTER X. 



this is in turn removed by absolute alcohol. The alcohol is 

 poured off, and the sections are covered with solution of 

 celloidin or with a solution of 3 per cent, of photoxylin or 

 Sobering' s " Celloidinwolle " in a mixture of equal parts of 

 ether and absolute alcohol. The plates are left to evaporate 

 for ten minutes in a horizontal position, then brought into 

 water, in which the sheet of celloidin with the sections soon 

 becomes detached, and may be further treated as desired, 

 e. g. as in Weigert's process, 195. (It is well to divide the 

 sheet of celloidin into ribbons by running the point of a 

 knife down it as soon as evaporation has produced a very 

 slight solidification, and the evaporation must not be artifi- 

 cially hastened.) 



This is the process for paraffin sections ; for celloidin sec- 

 tions the sections are taken up in order on a strip of paper 

 (glossed tissue paper, satinisirtes Seid&npapierj the sections to 

 be 011 the glossed side) as in WEIGEKT'S method, and laid 

 down on the glass in the same way, and then covered with 

 the celloidin or photoxylin solution and evaporated as de- 

 scribed. The advantage of Obregia's process is that it is 

 equally applicable to paraffin sections, to celloidin sections, 

 and to sections of material that has not been imbedded at all. 



DIMMER (Zeit.f. wiss. Mik., xvi, 1, 1899, p. 44; Journ. Roy. Mic. Soc., 

 1899, p. 448) coats the slides with a solution of about 16 parts of gelatin 

 in 300 of warm water, and dries them (two days), and proceeds in other 

 respects as above. 



197. GIACOMINI'S collodion-gelatin process for large sections, see Gazzetta 

 delle Cliniche, November, 1885, Zeit. f. wiss. Mile., 1885, p. 531, or the 

 first edition of the Traite of LEE et HENNEGUY, p. 392. 



