766 



SCIENCE 



[N. S. Vol. XLII. No. 1091 



this letter were to clear up any misunderstand- 

 ing as to priority on behalf of Dr. Lhamon, no 

 reply would be required, but since the letter 

 is so written as to suggest that an attempt has 

 been made by my associate, Dr. Alfred Oohn, 

 to unjustly obtain credit for this discovery, it 

 seems that a reply is demanded, especially 

 since Dr. Meyer has apparently drawn conclu- 

 sions concerning Dr. Cohn's motives which 

 are quite out of harmony with what his 

 friends know of his character. 



I am quite familiar with the work that Dr. 

 Cohn has done on this subject, and have now 

 carefully reviewed the publications in question, 

 and also have seen the correspondence which 

 has passed between Dr. Cohn and Dr. Meyer. 

 In the light of all that I can learn in regard 

 to the matter, it would seem that so far as the 

 actual matter of priority is concerned Dr. 

 Meyer is needlessly alarmed, and it is very un- 

 likely that in future generations any one is 

 going to claim that Dr. Oohn was the first to 

 prepare such injections. Dr. Cohn himself, in 

 a letter to Dr. Meyer which Dr. Meyer quotes, 

 has stated that " so far as priority is con- 

 cerned, not only I, but every one acquainted 

 with the subject, gives and has given full credit 

 to Lhamon." 



The chief purpose of Dr. Meyer's letter, 

 therefore, seems to be to take Dr. Cohn to task 

 for having presented before the New York 

 Pathological Society in December, 1911, ox 

 hearts showing injection of the conducting 

 system. These hearts were prepared by Dr. 

 Cohn for purposes of demonstration in the 

 Hospital of the Rockefeller Institute, in order 

 to make more clear the discussion of lesions of 

 the conducting system. The idea of carrying 

 out such injections came from a conversation 

 with Dr. MacCallum, in which the latter stated 

 incidentally that he had seen hearts at Stan- 

 ford University with conduction system in- 

 jected. Dr. Cohn at this time was no longer 

 a member of Dr. MacCallum's staff, having 

 been appointed associate in medicine in the 

 Hospital of the Rockefeller Institute. Dr. 

 MacCallum told Dr. Cohn nothing of the de- 

 tails of the method, nor did Dr. Oohn have 

 any communication with Dr. Oppenheimer on 



the subject, but he experimented quite inde- 

 pendently, and, after trying various dyes, 

 finally succeeded in preparing some beautiful 

 specimens, using India ink for the purpose. In 

 his demonstration of these specimens before 

 the staff of the hospital at our weekly meeting. 

 Dr. Cohn made no claim, and made no attempt 

 to lead the staff to infer, that he was the first 

 to discover that such injections might be made, 

 or that he was the discoverer of a method of 

 making such injections. Indeed, all the mem- 

 bers of the staff, including myself, fully under- 

 stood otherwise. Dr. Cohn did not state who 

 had first made such injections, however. In- 

 deed, as he tells me, at that time he did not 

 know the name of the person who had done so. 

 The injected hearts were so beautiful and 

 instructive that at a meeting of the Patholog- 

 ical Society, occtu-ring shortly after they were 

 made, he demonstrated them to the members 

 present. At this meeting no attempt was made 

 to claim credit for the method. Indeed such a 

 claim would have been preposterous, since Dr. 

 MacCallum, the president of the society, had 

 himself told Dr. Cohn of seeing such injections 

 in California. So far as can be learned, no 

 one at the meeting of the Pathological Society 

 was deceived by Dr. Oohn, and no attempt was 

 made to deceive. The Proceedings of the 

 Pathological Society which are published con- 

 sist mainly of brief notes, in the form of ab- 

 stracts of the remarks of those making demon- 

 strations or reports. In the volume for 1911 

 appears such a report, one page in length, con- 

 cerning Dr. Cohn's demonstration. Previous 

 to the meeting Dr. Cohn had made no notes, 

 and his demonstration was entirely informal. 

 This demonstration by Dr. Cohn was in no 

 way considered as a publication. No effort 

 had been made to find any literature concern- 

 ing this subject, and the demonstration was 

 not given with any idea of establishing prior- 

 ity, or indeed of obtaining any credit for dis- 

 covery of a new method. It is quite true that 

 Dr. Lhamon's name was not mentioned at this 

 demonstration, and his name does not appear 

 in the note published in the Transactions. This 

 is indeed unfortunate and if it has led, or were 

 likely to lead, to any misunderstanding, I am 



