94 PHYSIOLOGY AND TOXICOLOGY 



Iccting the fluid for observation tlie dog suddenly discharged per anuni at least 

 four ounces of dai'k, gnunous blood. At this time I supplied the dog with water, and 

 left him. Fifty-four hours after the bite he was seen again, and found to have 

 drunk freely of water, and to have passed fewer stools. Up to this date he declined 

 all food. 



From this time he improved rapidly, and took with eagerness whatever nutri- 

 ment was offered. On the fourth day his blood again exhibited a clot, although it 

 was very small and of loose texture. I made no further examinations of the blood. 

 The dog lost flesh as he gained strength, and had profuse suppuration from an 

 abscess in the bitten flank. At the close of two weeks he was active and well, 

 except that the wound was still open. 



The case last rented is doubly valuable, as pointing out even in a single instance 

 the time at which the blood became altered, and also as showing, once more, how 

 profound may be this change, and how perfect the recovery. 



The study of envenomed blood has thus far taught us — 1st. That in animals 

 which survive the poisoning for a time, the blood is so altered as to render the 

 fibrin incoagulable. 



2d. Experiments in and out of the body have given proof that this change is 

 gradual, and that the absence of coagulation is not due to checked formation of 

 fibrin, but to alterations produced by the action of the venom in that fibrin which 

 already exists in the circulating blood. 



3. The influence thus exerted is of a putrefactive nature, and imitates in a few 

 hours the ordinary results of days of change. It is probably even more rapid 

 within the body, on account of the higher temperature of the economy. 



4th. The altered blood retains its power to absorb gases, and thus to change its 

 own color. 



5th. The blood-corpuscles are unaffected in acute poisoning by Crotalus venom, and 

 are rarely and doubtfully altered in the most prolonged cases which result fatally. 



6th. The contents of the blood-globules of the guinea-pig can be made to crystal- 

 lize as is usual after other modes of death. 



Altered Relation hetween the Blood and Tissues. — Among the most constant and 

 most curious lesions in the cases of secondary poisoning are the ecchymoses which 

 are found on and in the viscera of the chest and belly ; most frequently afiecting 

 the intestinal canal, they may and do occur in any cavity and on any organ. These 

 spots contain blood whose globules are more or less deformed, but still of dimensions 

 not less than usual. As they do not take place until the blood is considerably 

 altered, and as the intra-vascular blood-disks undergo no apparent change, this 

 leakage of the blood into the serous cavities and areolar interspaces is plainly due 

 to the loss of coagulating power in the blood, or to alterations in the vascular tubes, 

 or perhaps to both. Unfortunately, we can but revive anew the unanswered 

 question as to the possibility of the escape of blood-disks through yet unwounded 

 vessels. It is likely, however, that the tissues share in the incipient putrefactive 

 fermentation which characterizes prolonged cases of this poisoning, and are more 

 or less weakened thereby ; so that, with a degraded blood, and, of a consequence, 

 with an embarrassed capillary circulation, aided by laboring respiration, we can 



