174 



IMBEDDING METHODS. 



you try to cut in paraffin objects of somewhat greater size, 

 10 mm. and upwards, it will probably happen that you will not 

 get perfect sections at all, blocks of paraffin of this size having 

 a tendency to split under the impact of the knife ; so that for 

 large objects celloidin gives better results. 



I have not been able to satisfy myself that the preservation 

 of the tissues is better in celloidin sections than in paraffin 

 sections; so that convenience apart the case remains as 

 above stated, paraffin for small sections, celloidin for large 

 ones. 



To this must be added aqueous masses, such as gum or 

 gelatin, for very special cases. 



It will be the purpose of the next chapter to describe the 

 paraffin method, and to mention some other masses that can 

 be employed in a similar manner, the celloidin method and 

 the other methods that remain to be described being treated 

 of in Chap. XYI. 



