VIU PREFACE 



luiiid, \aii()us exjx'i iniciital altcinj)ts were made which hardly 

 need any detailed description in this monograph. They were in- 

 tended to ()\'erc()me a hypothetical natural state ot resistance as- 

 sumed to exist in the annual cell. In some experiments, rabbits 

 received intraocular injections of B. typhosus culture filtrates 

 with subsequent intracranial injections of the same filtrates; in 

 others, leucocytes cidttned in vitro, according to Carrel's tech- 

 nique, \vere repeatedly exposed to bacterial culttne filtrates at 

 various intervals of time. The residts were suggestive Ijut rather 

 too indehnite for publication. Following these preliminary experi- 

 ments, the phenomenon of local skin reactivity to bacterial 

 filtrates was oliserved by me in September, 1927 (1928 a, b) . Re- 

 capitidation of extensive experimental work on the phenomenon 

 thus far accimiulated; together with a review of certain previously 

 knoAvn facts directly belonging to related fields, are embodied in 

 this monograph. The scope of this book, intended for presenta- 

 tion of original observations directly pertaining to the phenom- 

 enon of local skin reactivity to bacterial filtrates made by various 

 in\estigators and myself, does not allow a thorough sinvey of the 

 related literattue. 



Attempts w^ere made to divide the material into chapters each 

 consistently dealing ^vith a separate topic. Repetitions Avere tui- 

 a\oidable because of close inter-relationships between certain ob- 

 servations and because of their \arious implications. 



The monograph includes data published by various investiga- 

 tors and myself uj) to the beginning of 1936 and also personal 

 unpublished obser\'ations made by me dining the past se\'en years 

 up to date. 



Inasmuch as the ^vork thus far done has demonstrated certain 

 definite relations of this phenomenon to various immunological 

 processes; to pathology in general; and to problems of biological 

 therapy, the presentation of the monograph to the medical pro- 

 fession seems to be justified.^ 



^ Small print is used for technical descriptions, protocols and special facts. 

 Readers desiring to obtain only general information concerning tlic phenomenon 

 may omit the reading of the small print. 



Gregor-^' Shwartzman 

 Nexu York, N. Y. 

 August, 1937. 



