302 



PARAFFIN METHOD 



[ CH. X 



449. Deparaffining in Xylene. This is accomplished by 

 using a solvent of paraffin. The best and safest one to use in a 

 laboratory is xylene. Benzine, gasoline, and even kerosene are 

 used, but xylene is a powerful solvent of paraffin, does not injure 

 the tissue, and is not very inflammable, due to the large amount of 

 carbon in its molecule (see 392). 



It requires only a few minutes to dissolve paraffin from the sec- 

 tions, but a day or more in the xylene does no harm. 



When the paraffin is removed the staining and other operations 

 necessary for a completed preparation may be undertaken (See for 

 these 461-471). 



FIG. 243 FIG. 244 



FIG. 243. Slide basket or holder and a glass stoppered bottle to contain 



the same. Xylene is safer than benzin for deparaffining. The slide basket was 



devised by Dr. A. B. Mix in the author' slab oratory in 1898. It is cylindrical 



and has an unjointed handle or bail. (Jour. Ap. Micr., vol. i, s8o8, p. s6o). 



FIG. 244. Square slide basket with hinged bail or handle so that it may 

 t be turned down in inserting or removing the slides. In 1900 the hinged bail 

 was added to the round slide baskets, and in 1902 the form was changed from 

 round to square. The square form is more convenient, and suitable for all 

 sizes of slides. ( Cut loaned by the Spencer Lens Co. ) . 



450. Collodionizing the Sections. Except for carmine 

 stains and perhaps some others, collodion remains practically color- 

 less. While the sections remain quite firmly attached to the slide 

 after they have been spread and dried, thick sections are liable to 



