154 Mr. G. F. Dowdeswell. Action of Heat [June 15, 



cooled ; it was maintained at a temperature of over 100° C. for upwards 

 of one hour. It being then late in the evening, rabbit No. 4 was on 

 the next morning injected with a Pravart's syringe fnll of the dilute 

 superheated blood. This animal survived and was but slightly, if at 

 all affected, notwithstanding the very large quantity of fluid injected. 

 The following day there was no appreciable disturbance whatever, 

 but on the third day slight pyrexia occurred, the animal's skin felt 

 hot to the touch, and the rectal temperature rose to 10O0° F., which, 

 however, sometimes occurs normally in rabbits kept in confinement. 

 Subsequently, it remained totally unaffected for several days, as long 

 as observed, and was then destroyed. 



Some days afterwards, the blood of another rabbit of a subsequent 

 generation of the same infection, immediately upon death, was mixed 

 with two parts normal saline solution, and 2 per cent. pot. carb., 

 this was inclosed in tubes, boiled, sealed, and heated to 120° C, in 

 the same manner as before. 



Of the alkaline dilute blood (unheated) further diluted up to 

 100,000,000 times, 0'6 cub. centim. (='000000006 cub. centim. of 

 blood) was injected into the back of rabbit E, which died of septi- 

 chaemia within twenty hours. 



Of the dilute superheated blood, 0*6 cub. centim. (=0*2 cub. 

 centim. blood) was injected into rabbit F, which the next day was 

 apparently unaffected, but died with the usual symptoms of septichsemia 

 the following day, i.e., thirty-nine hours after injection. In the blood 

 were found the characteristic Bacteria, and it proved to be infective 

 when injected in a small quantity into another rabbit. Upon this, the 

 same day, a further portion of the same superheated dilute alkaline 

 blood was injected in the same quantity (0'6 cub. centim.) into 

 rabbit G. This rabbit remained totally unaffected, and survived as 

 long as observed, twenty days after, although it had received upwards 

 of 30,000,000 times the quantity of blood which had proved lethal to 

 rabbit E within twenty hours. 



Cultivation experiments have been made both with the superheated 

 blood and with that in the natural state, taken upon death ; but as it 

 was found that the Bacterium which occurs in these cases refuses to 

 germinate in any of the various cultivating media employed, except- 

 ing only in the serum of ox-blood, and in that very sparsely and 

 uncertainly, they were inconclusive; and the greater part of the 

 cultivating glasses inoculated with blood of both sorts, after being kept 

 several days in the incubator at temperatures between 30° and 40° C, 

 unstable as the solutions are, remain to this day — a month subse- 

 quently — perfectly pellucid and unaltered, save from some loss by 

 evaporation. 



On considering these results, it appeared possible that, in the case 

 where the superheated blood proved infective, from the method of 



