Embedding Tissues' and Section- Cutting 139 



Cole's Microtome and Embedding in Carrot. When 

 a number of sections are wanted, or when a complete sec- 

 tion of an organ is desired, a microtome should be used. 

 A very good and simple instrument can be obtained from 

 Messrs. Watson and Sons, 313, High Holborn. Screw the 

 microtome firmly to the table, and with the brass tube 

 supplied with the microtome punch out a cylinder of carrot 

 to fit into the well of the microtome. Cut this in half 

 longitudinally, and scoop out enough space in one half of 

 the carrot to take the specimen ; then place the other half 

 of carrot in position, and make sure that the specimen is 

 held firmly between them, but it must not be crushed. 

 Now put the cylinder of carrot and specimen into the well 



FIG. 52. COLE'S PATTERX' MICROTOME. 



of the microtome and commence cutting the sections. A 

 good razor will do, but it is better to use the knife which 

 Messrs. Watson supply with the microtome. While cutting, 

 keep the knife and plate of the microtome well wetted with 

 dilute methylated spirit, and as the sections are cut place 

 them in a saucer of dilute spirit. A number of sections 

 may be cut and preserved in methylated spirit until required. 

 When a specimen has a very irregular outline, it cannot 

 be successfully embedded in carrot. Paraffin should then 

 be used. Place the tissue in the well of the microtome in 

 the desired position, pour in enough melted paraffin to 

 cover it, and when cold cut the sections. 



