98 BARON DIMSDALE AND INOCULATION CH. ix 



modified by repeated transmission through the bovine animal. 

 It then ceases to produce a general eruption, or to be infectious 

 in the ordinary manner, whilst still protective against the 

 major disorder. Dr. W. T. Councilman of Harvard University 

 has found certain minute bodies (cyto-ryctes) in the cells of 

 the tissues, having two forms : the one form (probably 

 asexual) is found in the protoplasm of the cell in cases of 

 vaccinia : the other form (probably sexual and rapidly multiply- 

 ing) is found within the cell-nucleus in the acute disease. 

 The life-history of the parasite depends upon its host : in the 

 calf or rabbit it follows the milder cycle only, and vaccinia is 

 the result : in man or monkey it goes on to the more active 

 cycle, and variola is developed, although in the case of the 

 monkey only the slighter* (inoculated) form occurs. The 

 doctrine of the attenuation of a disease virus by passage 

 through a living animal, which was founded by Pasteur and 

 others upon Jenner's original suggestion, has come to include 

 other diseases besides smallpox, especially rabies, typhoid 

 fever, cholera and plague ; and the prophylactic measures 

 thus derived hold the field, in the present state of our know- 

 ledge, as the best means of defence against these scourges of 

 the human race. 1 



1 Authorities : Woodville, History of Inoculation, 1796 ; see also Phil. 

 Trans. Iviii. 140 and elsewhere ; S. Miller, Retrospect of the Eighteenth Century, 

 P- 1354 ; Jas. Moore, History of Smallpox, 1815 ; Jos. Adams, Answers to 

 Objections to Cowpox, 2nd ed. 1805 ; also his Account of the Hospital for Small- 

 pox, Inoculation and Vaccination, 3rd ed. 1817 : he gives the mortality of 

 inoculated cases as follows: In-patients (9 years), nil; Out-patients (6 years), 

 i in 1000 (p. 27) : his strain of mild inoculated smallpox is recorded on pp. n, 

 12 ; Dr. E. M. Crookshank, History and Pathology of Vaccination, 1889, i. ; 

 W. Farr, Vital Statistics, pp. 304, 305 ; Sir T. Watson, Lectures, 1848, ii. ; 

 Dr. S. M. Copeman, Natural History of Vaccination, Milroy Lectures, 1899, 

 and Modern Methods of Vaccination, 1903 ; also article in Allbutt's System 

 of Medicine, 2nd ed. II. i. 746 ; Dr. F. M. Sandwith, Clin. Journ. Land, xxxvi. 

 317-329 ; Dr. W. T. Councilman, Journ. Med. Research, Boston, xi., Feb. 1904 ; 

 also in Osier and McCrae, System of Medicine, ii. 254, etc. ; Drs. W. G. Armstrong, 

 J. B. Cleland and E. W. Ferguson, of Sydney, N.S.W., Proc. Roy. Soc. Med. 

 Epidem. Sect., Nov. 1914, where an epidemic disease is described, said to be 

 a mild type of smallpox, occupying a half-way house between it and vaccinia ; 

 in one case parasites in the cell protoplasm were found. Was this identical 

 with " inoculated smallpox " ? In view of Dr. Copeman's researches on a 

 similar epidemic at Cambridge in 1903, was not the attenuation of the disease 

 due to bovine transmission ? It seems to have been brought by men working 

 on cattle-boats. 



