534 



Mr. E. C. Hort. 



[June 2, 



received subcutaneous injections of water in quantities varying from 10 to 

 60 c.c. With the former quantity a slight rise occurs, even in rabbits weighing 

 2^ kilogrammes, with the latter a marked rise, sometimes to 104-5'' F. or 

 40'3° C. Some elevation of temperature above the normal occurred in all 

 12 animals. An injection of 23 c.c. into a marginal vein of the ear of a 

 rabbit weighing 1-| kilogramme caused a rise to 106° F., or 41'1° C. 

 The rise in rabbits shows roughly the same abruptness, the same length of 

 time to reach the maximum, and the same fugitive nature as in guinea-pigs. 



2. Multijjle Injections. — The effect of multiple injections in both rabbit and 

 guinea-pig is to cause a continuous fever lasting only so long as the injections 

 are continued, abruptly ceasing as soon as the injections are stopped. 

 Multiple injections were given to 30 guinea-pigs and 10 rabbits, and caused 

 fever in every case. To several other guinea-pigs than these 30 injections 

 larger than 10 c.c. were given, and instead of a rise of temperature a profound 

 fall followed. The same effect can be produced by giving small injections, 

 closely spaced. On correct spacing of two injections into the same animal 

 hypersensitisation is frequently induced, within limits not yet determined, 

 but clearly evidenced by the rise of temperature induced by the second 

 injection being greater than that induced by the first. Owing to the 

 difficulty already mentioned of repeated thermometric observations extending 

 over several days in the guinea-pig, study of the effect of multiple injections 

 of more than two in number is unsatisfactory, but the effects of hypersensitisa- 

 tion in this animal after two injections are convincing. For study of the 

 effects of injections over a series of days the rabbit must be used. 



It is impossible to reproduce all the very numerous charts illustrating the 

 induction of fever after both single and multiple injection in the rabbit and 

 guinea-pig, but a few typical charts are subjoined for comparison with the 

 control charts given above. 



