254 



Mr. F. G. Jackson and Dr. Y. Harley. 



produced by the eating of tainted meat, and not by the want of fresh 

 vegetables. In order to confirm or negative this view, it was decided 

 to carry out some experiments in this country. After careful con- 

 sideration, it was concluded that the most suitable animals for such 

 experiments would be monkeys, since they are mostly nearly allied to 

 man. Monkeys are not naturally carnivorous, and therefore it would 

 be necessary to give the meat mixed with food that would not possess 

 any alleged anti-scorbutic properties; and for this ptu-pose it was 

 decided to feed the monkeys on boiled rice and maize. In order to keep 

 the standard of meat as nearly as possible always the same, a certain 

 brand of tinned Australian beef was employed. 



Daily the rice was well boiled, and, after becoming thoroughly 

 softened, 50 grammes of meat was added to each portion of rice for 

 the various monkeys. It was then well stirred and gently heated ; 

 by this means the meat got well mixed with the rice, and, although 

 the monkeys might reject some of the larger lumps of meat, a con- 

 siderable portion of it was eaten. At the same time any soluble 

 ptomaines would be absorbed by the rice, and thus eaten by the 

 monkeys. To this mixture daily was added a certain amoimt of maize. 

 The results can be best described by di"vdding the experiments into 

 three groups. 



First Group. — The monkeys in this group were given daily, together 

 with their boiled rice, 50 grammes of meat from a freshly opened tin, 

 together ^^T.th maize. 



Second Group. — The monkeys in this group were given the same 

 quantities of meat as in the previous group, but from tins which had 

 been opened for a few days, and had stood in the laboratory. The 

 meat in these was not what one would call bad, although it had a dis- 

 tinctly sour smell. Rice and maize as before. 



Third Group. — The monkeys in this series were given exactly the 

 same diet as was employed in the second group, except that each 

 monkey received daily either an apple or a banana. 



We have found in these three groups three conditions, so far as diet 

 is concerned, which ought to yield definite results in reference to the 

 subject of ptomaine poisoning. 



In order that the general surroimdings of the monkeys should be 

 iis nearly as possible the same, and that each should be properly 

 observed, every monkey was kept in a separate cage of similar con- 

 struction, so that the faeces could be easily examined. The cages 

 were kept in a room warmed by hot-water pipes, so that they were 

 under as nearly as possible similar conditions as regards light and 

 heat. The excreta of the monkeys were examined daily, and the 

 general appearance of the animals noted, more especially as regards 

 the condition of tne gums. Every few days they were weighed. 



We can now proceed to describe the results of the experiments. In 



