JOHN A. KOLMER 1123 



The double salt, quinin and urea hydrochlorid, was similarly without curative 

 value in doses as high as 0.04 gm. per kilo when given at intervals of an hour or more 

 after inoculation with 50 M.L.D. of culture. When the dose of culture was reduced to 

 10 M.L.D. a distinct efifect was evident in the prolongation of life four, five, and six 

 days among animals receiving o.oi gm. and more per kilo of body weight. 



By intramuscular injection ethylhydrocuprein in doses ranging from 0.02 to 0.06 

 gm. per kilo of body weight prolonged the life of a small percentage of mice and rab- 

 bits when given within two hours after infection with 50 M.L.D. of culture; smaller 

 doses in this time and similar doses given at longer periods were practically without 

 efifect. Hydroquinin hydrochlorid, quinin and urea hydrochlorid, and quinin bisul- 

 phate in doses ranging as high as 0.04 gm. per kilo of body weight were practically 

 without any effect when given within one hour or longer after inoculation with 50 

 M.L.D. of culture. Three of the cinchona derivatives were administered by repeated 

 intramuscular injections; ethylhydrocuprein hydrochlorid prolonged the lives of a 

 few more mice to the seventh day or longer than did the other cinchonics. It is prob- 

 able that the death of some of the mice was due to the cumulative effects of the 

 repeated large doses. 



Observing that antipneumococcus serum for type II pneumococci was less efifi- 

 cient than the serum for type I, Moore studied the influence of a combined optochin 

 and serum treatment for type II infections among mice, and found that a single dose 

 of optochin suspended in oil and injected subcutaneously, which by itself has prac- 

 tically no protective effect, was capable of increasing the threshold value of type II 

 serum at least fifty times, and that this effect was proportionately many times greater 

 than a simple summation of the protective and curative effects of the two substances 

 separately. Steinfield and myself also observed that ethylhydrocuprein hydrochlorid 

 by subcutaneous injection in doses without protective value usually increased the pro- 

 tective value of antipneumococcus serum type I in a slight but definite manner in 

 severe infections of mice and rats with homologous pneumococci. Several of the com- 

 moner compounds of quinin, as quinin and urea hydrochlorid, quinin bromid, and 

 quinin chlorohydrosulphate, given subcutaneously in doses without any appreciable 

 influence on severe and fatal pneumococcus infections, occasionally increase the pro- 

 tective power of antipneumococcus serum but to a lesser extent and less regularly 

 than ethylhydrocuprein hydrochlorid. 



Idsumi and I have also observed that the sub thecal injection of single doses of 

 ethylhydrocuprein in amounts of 0.5 cc. of 1:500 and 1:1,000 solutions per kilo of 

 body weight had a distinct beneficial effect on the course of experimental meningitis 

 in rabbits produced by a type I pneumococcus of moderate virulence, when admin- 

 istered not later than four to six hours after the injection of organisms; when given 

 twenty-four hours after the pneumococci this effect was not apparent. With a men- 

 ingitis produced by a more virulent culture of type II pneumococci, single doses of 

 this drug had but slight or no effect on the duration of the lives of the experimental 

 animals; but in experiments consisting in the repeated subthecal injection of smaller 

 doses of pneumococci followed in a few hours by ethylhydrocuprein, the protective 

 and curative effects of the drug were more apparent. 



Lamar has shown in the treatment of experimental meningitis of monkeys that 



