COLLODION, CELLOIDIN 3 AND PHOTOXYLIN. 193 



CHAPTEK XYI. 

 COLLODION (CELLOIDIN) AND OTHER IMBEDDING METHODS. 



297. Collodion, Cello idin, and Photoxylin. The collodion 

 method is due to DUVAL (Journ. de VAnat., 1879, p. 185). 

 Celloidin, recommended later on by MERKEL and SCHIEFFER- 

 DECKER (Arch. f. Anat. u. Phys., 1882, p. 200), is merely a 

 patent collodion. 



It is stated to be a preparation of pure pyroxylin, and is 

 patented for Germany and England under the name of 

 " Schering's Celloidin." It is manufactured by the Chemische 

 JFabrik auf Actien (vorm. E. Schering), Berlin, N. Fenstrasse 

 11, 12. It may be obtained through the post by writing to 

 SCHERING'S " Griine Apotheke," Wittick and Benkendorf, 

 Berlin, N. Chaussee-Strasse, No. 19, or from GRUBLER, or the 

 other dealers in histological reagents. 



It is stated to be prepared with the purest pyroxylin, and 

 to be always of a uniform composition. It is sent out in the 

 form of tablets of a tough gelatinous consistency and slightly 

 milky- white transparency. These tablets contain 20 per cent, 

 of pure pyroxylin. Celloidin is entirely soluble, in all pro- 

 portions, in ether and alcohol. It is free from acids. It is 

 not detonant. If ignited it burns like paper ; heated in a 

 test-tube it carbonises without exploding. 



In order to make a 2 per cent, collodion, take one tablet of 

 celloidin (which contains 40 grms. of the dry pyroxylin), and 

 such a quantity of alcohol and ether that the whole shall 

 weigh 2000 grms. For a 3 per cent, collodion you take such 

 a quantity of alcohol and ether that the whole shall weigh 

 1333 grms. ; and for a 4 per cent, collodion such a quantity 

 that the whole shall weigh 1000 grms. The relative portions 

 of alcohol and ether may be taken according to discretion. 

 To prepare a medicinal collodion according to the Prussian 

 Pharmacopoeia you take for each tablet 720 grains of ether 

 and no alcohol, as the celloidin already contains the prescribed 



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