92 ESSAYS ON BACTERIOLOGY. 



theria germ, so there may be, and probably are, cases 

 of membranous laryngitis non-dipbtheritic in charac- 

 ter. And so the old question is not yet fully settled. 

 The imm.ediate future, we can hardly doubt, will 

 bring the full and satisfactory solution. 



As to the antitoxin treatment of diphtheria, the 

 writer feels disposed to give it a large place, since it 

 belongs now to both bacteriology and clinical medi- 

 cine, though entirely an outgrowth of bacteriology. 



In a former address emphasis was laid upon the im- 

 portance of getting a clear view of the established 

 facts as distinguished from the theories, and of keep- 

 ing these facts in mind as a guide to right-thinking 

 and acting. At that time the things which we seemed 

 warranted in accepting as demonstrated were these: 

 that there is a germ in diphtheria, which, being inocu- 

 lated in pure cultures, will kill ; that this germ, being 

 artificially cultivated, produces an intense poison 

 which will kill; that, by the injection of gradually in- 

 creasing quantities of this toxin into certain animals, 

 they may acquire an enormous resisting power to it 

 and to the germs; and that by the transfer of their 

 blood serum this resisting potver might be transferred 

 for a limited time to other animals, and be for them 

 an almost specific preventative of diphtheria and al- 

 most equally specific cure of the disease in its earlier 

 stages. These, which seemed worthy of acceptation 

 as demonstrated facts, remain as they were, though 

 their explanation still ekides us. 



