METHOD OF EMBEDDING. 



143 



or tin vessel (a small oil-can answers the purpose 

 very well), and heated over a water-bath until the 

 wax is entirely melted. The mixture is then thor- 

 oughly stirred, and put aside until wanted. In 

 laboratories where it is likely to be much in requisi- 

 tion it is well to have a supply always ready melted. 

 This may be done by keeping it in a sandbath at a 

 temperature of about 40 C. 



Process of embedding, One or more shallow 

 oblong moulds of different sizes should be kept in 

 readiness for embedding pieces of tissue in. They 

 may be made of thin pliable metal, such as sheet 

 lead or capsule metal (Fig. 23), so as to permit the 

 sides to be readily bent back and the wax-mass 

 removed when set; but if these are not at hand a 

 suitable mould may always be extemporized out of 

 ordinary stiff paper. A piece is cut of about the 

 size and shape shown in the accompanying diagram, 

 Fig. 21, and folded along the lines there marked out, 



Fig. 21. 



Outline showing the manner in which a small piece of paper is to be 

 folded to make an embedding trough. 



the small dotted diagonals at the corners being scored 

 with some blunt-pointed instrument, an ordinary 

 hard lead pencil, for instance. These corners are 

 then pinched up between the finger and thumb, 

 bent round so as to be applied to the ends of the 



