504 Second European Journey 



I have read your monograph with very great interest and think it a 

 valuable contribution to the subject of growth, but you will forgive me if 

 I fail to see the exact relation to tumors. The fact that growth can be 

 stimulated in various ways, both mechanical and chemical, or possibly the 

 mechanical would resolve itself ultimately into the chemical, is a very 

 important fact. There is such an enormous difference between the multi- 

 potent tissues of the plant and that of the animal. The explanation of 

 tumors, when it comes, must take in all cases, the congenital and the senile 

 tumors, as well as those in between. I feel that the senile tumors, which 

 are more prominent in animals than in man, play a very great part, asfor 

 instance in dogs, where we get a general tumor formation which affects 

 the tissues generally it is true, but certain tissues very much more, and 

 where the tumors are never unicentric but multicentric. I think, however, 

 that you should follow out your work continually, and that it does throw 

 light on tumors in enabling us better to comprehend the essential factor 

 which is growth. 



In 1924 Smith and Councilman would meet in Rome, Italy, and, 

 with crown gall photographs and actual tumor specimens from 

 live oak trees before them, plant pathologist would explain more 

 fully to medical pathologist the points of analogy between plant 

 and animal tumors. '° 



From Philadelphia, Chicago, St. Louis, and many other cities 

 over the country highly reputable surgeons sent Smith letters 

 expressive of interest in, and appreciation for, the value of his 

 research disclosures. A few may be listed: Dr. Herman Morris 

 Adler, Dr. Henry W. Abelmann, Dr. M. G. Seelig, Dr. Solomon 

 Solis Cohen, Dr. Henry W. Stelwagon, Dr. Arthur A. Eisenberg, 

 Dr. Bradley M. Patten, Dr. Andre Crotti, Dr. RoUin Howard 

 Stevens, and many others whose letters or work will be considered 

 elsewhere in this book. Dr. Adler wrote: " Together with all the 

 pathologists of the world, I have been extremely interested in 

 your work." Some of these doctors, interested in research, began 

 experiments of one sort or another making use of the crown gall 

 organism. For instance. Dr. Stevens obtained cultures of Bacter- 

 lum tumefaciens, transplanted them several times on plain agar, 

 and inoculated several red geraniums, all with a view to studying 

 the effect of X-ray on the viability of the cultures, the tumor pro- 

 duced, and on immunity of the plant. He called to Smith's 

 attention a recent editorial in the Journal of the American Medical 



'•"See p. 610 of this book. 



