546 Crown Gall-Animal Cancer Analogy 



and added, " It seems as if a parasite might be cultivated from 

 it. . . ." That day Dr. William H. Woglom accepted for publica- 

 tion in the journal of Cancer Research Smith's manuscript, "Appo- 

 sitional Growth in Crown-Gall Tumors and in Cancers." 



Later that year, on December 8 at Detroit, Dr. Francis Carter 

 Wood of the Crocker Institute told Smith that they now had 

 " over 800 rat liver sarcomas from feeding eggs of the cat tape- 

 worm." He added to his diary memoranda that these had " come 

 along very rapidly in the last six months and they have had 100% 

 of cases in descendants of Sarcomatous rats bred together, but 

 none without the irritation of the worm." This last fact was to 

 Smith significant since it tended to minimze, without dispelling, 

 the hereditary aspect of cancer and did not disturb the suscepti- 

 bility aspect. 



He regretted that time did not permit him to visit the botanists 

 and zoologists of his acquaintance at the Rockefeller Institute. 

 The end of the week had arrived and by the beginning of the next 

 he had to be in Washington. Reaching there, he on May 31 

 assembled his photographs, and again re-studied parts of his paper 

 on appositional growth. He was yet to go to some research centers 

 and libraries in the middle west to settle a few final points. But, 

 before doing this, Dr. Brandes, now with the Department at 

 Washington, brought him a copy of a paper by L. O. Kunkel on 

 corn mosaic in which were figured certain intracellular bodies 

 associated with mosaic disease in Hippeastruni equestre and corn 

 in Hawaii. After their interview. Smith prepared another entry for 

 his diary: " Iwanowski in 1903 in Zeit[schrift'] /[/i'V] Pfi[anzen']- 

 krlankheiten~\ has a long paper on Tobacco mosaic in which he 

 figures the Kunkel bodies. [D.] Prain has recently named the 

 small bodies which Iwanowski saw, as a protozoan . . . and says 

 it is the parasite but offers no proof." 



In the early 1920's comparatively little was known of the 

 chemical composition of viruses and their physical mechanisms. 

 The stronger optical instruments with vastly improved lighting 

 facilities of today were then not available, at least not in quantity. 

 Superior instrumentation and special apparatus for various pur- 

 poses of investigations were being invented and perfected. Tech- 

 niques of filtration, as distinguished from ultrafiltration, and cen- 

 trifugalization, as distinguished from ultracentrifugation, in cancer 



