462 



Mr. G. F. Dowdeswell. 



[Jan. 18, 



From the above-mentioned animal of the second generation that died 

 infected, 0'22 cub. centim. of the serous fluid diluted was injected into 

 another guinea-pig, No. 14, which died within four hours, but 0*22 of 

 the exudation in it, being similarly injected into another, No. 15, of 

 the fourth generation, this survived for twelve hours, and was found 

 dead some hoars subsequently, showing that, as judged by the period 

 of incubation, the septic fluid was inferior in virulence to that of a 

 prior generation. Infection was continued through another generation, 

 the fifth, by injection of the same quantity of serum of No. 15 into 

 another animal, No. 16, of which finally 0*2 cub. centim. was injected 

 into No. 17 of the sixth generation in succession, which died in about 

 the same period after inoculation, viz., four to five hours, as had the 

 one previously of the third generation. The following successively 

 diminishing quantities were then injected into other animals, viz. : 

 0*022 cub. centim., 0*0022, and 0*00022 cub. centim., and some smaller 

 quantities still, all alike without producing any material symptom 

 of disturbance. In every instance here the Bacilli were present in 

 such numbers in the exudation serum from which the dilutions were 

 made that the smallest quantities injected must have contained very 

 many of them.* 



In regard to the relation of these micro-organisms to the diseases 

 in which they appear, it has been assertedf that they occur normally in 

 the blood of healthy animals, and are only enabled to develop by the 

 pathological condition caused in these cases by the injection of septic 

 matter. As this point is of fundamental importance to the subject, 

 to determine it experimentally, a young healthy rabbit, nearly full- 

 grown, was killed by asphyxiation, and then placed in the incubator 

 intact, for twenty -four hours ; at the end of that time the abdomen 

 was largely distended with gas, and putrefaction obviously well 

 advanced. On examination there was found in blood from the heart, 

 in rather small numbers, a Bacillus, the cells of which were of consi- 

 derable width, but of no great length, nor forming long chains, 

 mobile, and evidently in active multiplication, in some few cases 

 apparently forming spores at one end only ; there were a very few free 

 spores, but growing cells in all stages of development; no small 

 Micrococci nor any other species of Schizophyte, no B. termo, nor any 

 one of the organisms here described as specifically distinctive of 

 Davaine's septichaomia. In blood from the lungs and the liver the 

 same Bacillus also occurred, as it did in the spleen, but in smaller 

 numbers. In none of the organs or tissues examined was any other 



* In the experiments here recorded " infection " was originated by the intra- 

 peritoneal injection of a chemical irritant ; in other series, by putrid matter ; the 

 results are substantially the same in both cases. 



f Most recently by Professor Rossbach, " Vermehrung der Bakterian in lebenden 

 Tiere, &c," Ctbl. f. d. Med. Wise., 1882, No. 5, p. 82. 



