THE ORDINARY METHODS OF PREPARING TISSUES. 17 



up the specimen so that it may be sliced off by an ordinary 

 knife. For some purposes it is very useful. 



Freezing section- cutters. Of these there are many in use, 

 and they have certain advantages. In conjunction with Dr. 

 J. H. Hunt, of Brooklyn, I have devised a modification of the 

 ordinary instrument. 1 (Fig. 9.) 



FIG. 9. Freezing section-cutter : B, metallic box ; S, cylinder; a, well; c, c, frame for holding knife 

 A, A ; G, indicator ; D, milled head ; F, F, plugs ; E, E, tubes to fit in well ; H, H, covers to metallic 

 box ; K, binding screw attaching box to table. 



It consists of the brass cylinder, S, made of rather large 

 size, and placed in the centre of a metallic box, B. The 

 length of the cylinder, with driver, D, is about five inches. The 

 diameter of the well, a, measures If inch. Fitted round and 

 about the cylinder is a plate of glass which from its smooth- 

 ness permits the knife to sweep it easily. 



The knife, A, A, is large, measuring 13 inches in length, in- 

 cluding handle ; in breadth, If inch. It is fitted into a brass 

 frame, c, c, 7J inches in length and 3i in breadth. Two strong 

 brass springs, and two sliding clamps, hold it in place. The 

 knife is slightly concave on both sides. 



The well is so large that it will hold an ordinary kidney 

 after hardening, or at least so much of it that a transverse sec- 



1 Made by Miller Bros., 1213 Broadway, New York city. 

 2 



