82 



BACTERIAL DISEASES OF PLANTS 



good microscopes are the principal equipment required for the 

 preparation and study of permanent sections. 



Microtomes. — Zoologists generally, especially those who 

 have studied in Europe, seem to prefer the Jung or the Reichert 

 sliding microtome for section cutting. The writer has used both, 

 having first learned to cut sections on the Jung, but for many 

 years we have used almost exclusively a rotary Dutch machine 

 made at Delft and known as the Reinhold-Giltay. Dr. Charles 

 E. Bessey was, I believe, the first person in this country to use 



Fig. 53.- 



-Freezing microtome made by the Spencer Lens Co., Buffalo, N. Y., 

 with cylinder of compres.sed carbon dioxide. 



this machine and his high praise of it induced the writer to order 

 one for the Laboratory of Plant Pathology. All that was said 

 by Dr. Bessey in praise of this instrument has been more than 

 borne out by our experience with it. The machine we first 

 bought (for figures of it see "Bacteria in Relation to Plant 

 Diseases," Vol. I, 1905, pi. 13 and Fig. 119) is still in use and 

 nothing has ever been spent on it for repairs. In recent years, 

 with increase of our work, one microtome proved insufficient, 

 and we purchased a second machine of the same make. This 

 microtome is better, I think, than that similar and more recently 



