626 LABORATORY HINTS 



bath of melted paraffin wax six to eighteen hours ; the 



paraffin must be kept melted. The paraffin that is most 



useful for all purposes is that having a melting point of 



50° to 60° C. 

 Skin tissues become friable if kept long in the melted paraffin. 

 After impregnation of the tissue it must be embedded. 

 Pour a little paraffin wax into a small (pill) box, place the 



block of tissue in the centre and fill the box with wax. 



When set remove the box and attach to the plate of the 



microtome. 



(5) Mounting Sections on Slides. 



Place section in a dish of warm water so that the paraffin is 



softened but not melted, then the sections become flat. 

 Introduce a slide into the water under the section and raise it 



out of the water, adjusting it with a needle. 

 Dry in warm incubator for two hours. 

 If the sections are thick it is preferable to smear the slide first 



with egg albumen mixture to make the section adhere 



sufficiently for staining, 



For individual sections place a few drops of water on the 



slide, float section in it, and warm over a flame until it 



straightens out. 

 Pour off the water and the section will adhere. 



To Stain Sections. 



Remove paraffin with xylol and the xylol with spirit and the spirit 

 with water. This is unnecessary if it is not a paraffin section. 



Stain with haematoxvlin two and a half minutes, and flush with 

 water until blue. 



Stain with eosin ten seconds and wash with water. 

 Treat with spirit to remove water, then with clove oil. 

 Treat with xylol and mount wilh Canada balsam. 

 Never let the section dry. 



To tell if completely dehydrated when using clove oil place 

 on a dark slab, when it will appear milky as long as water 

 remains in the section. 



To show Parasites and Bacteria. 



Remove the paraffin with xylol, spirit and water as above. 



Stain with strong carbol-thionin ten minutes. 



Pour off and blot lightly. 



Treat with spirit rapidly, two dashes only. 



Treat with oil of cloves until transparent. 



Treat with xylol and mount with Canada balsam. 



