DISEASE-GERMS. 255 



Dr. Martin terms it) never succeeding beyond the third remove f rom 

 the human into the bovine subject. 



There can now, therefore, be no reasonable doubt that a very large 

 proportion of the failures, triumphantly adduced by anti-vaccinationists 

 as proofs that the alleged protective power of vaccination is a mere 

 assumption, are attributable to this degeneration, the protection 

 diminishing with the " humanization " of the virus employed, and this 

 being proportional to the remoteness of its derivation from the bovine 

 stock. 



During the war between the Northern and Southern States, Dr. 

 Martin (who had previously acquired a reputation for special knowl- 

 edge of this subject) was specially employed by the Government of 

 the North to proceed to the various localities in which severe outbreaks 

 of small-pox were from time to time taking place, and he most com- 

 monly found that there had either been no previous vaccination at all 

 or vaccination with degenerate virus. Armed with a supply of good 

 lymph, and with military authority (which enabled him to practice 

 a really compidsory vaccination and revaccination), he always found 

 himself able to control these outbreaks, and to prevent their recurrence. 

 Anxious, however, to obtain (if possible) a fresh primary stock of vac- 

 cine, he advertised extensively for information as to any original case of 

 cow-pock, but could hear of none. And he then imported from France 

 some dried lymph of what is known as the " Bougival " stock, which 

 had been continuously transmitted, through a long succession of 

 heifers, from its original bovine parentage in that place. This trans- 

 mission he has himself kept up in the neighborhood of Boston (New 

 England) for the last ten years ; and he assures me 1. That vaccina- 

 tion from this heifer-stock, if practiced according to his instructions, 

 is quite as successful (in regard to the proportion of cases in which it 

 "takes") as vaccination from the human arm; 2. That the vesicle 

 produced by it is always of the true old Jennerian type, no deterioration 

 having taken place in its long descent from the original stock, such as 

 is produced by " humanization " ; 3. That he has never seen either ery- 

 sipelas or any other of the " accidents " which sometimes (as in my 

 own Bristol experience in 1838) attend the direct vaccination from the 

 original cow-stock ; and, 4. That, having offered a considerable reward 

 in all the principal towns of the Union for information as to the 

 occurrence of any case of small-pox within ten years after thorough 

 vaccination with his heifer-lymph, this reward has never been claimed ; 

 although, since its introduction, the United States have been traversed 

 (in the years 1874-'76) by an epidemic of small-pox, which will be 

 long remembered there for its peculiar virulence and the wide-spread 

 mortality it occasioned.* 



* The distinguished American physicians, whose attendance at the recent Congress 

 gave me the opportunity of conversing with them on this subject, entirely confirmed Dr. 

 Martin's account of the severity of that epidemic, which, in some respects, bore such a 



