36 THE TONER LECTURES. 



found high up in the left external carotid, on which a secon- 

 dary thrombus had formed nearly down to the bifurcation of 

 tlie primitive carotid. Pain appeared from the jaw to the 

 temple on the twentieth day of typhoid, two days later the 

 ear was cold and violet, the arterj^ pulseless, and the gangrene 

 rapidl^^ extended to the entire left side of the head and face, 

 involving even the bones. I have found, however, but eight 

 other cases in which the embolic nature of the primar^^ obstruc- 

 tion was clear; but often the want of a minute examination of 

 the clot renders the report useless ; and sometimes probably 

 the primary' embolus is so overshadowed in size and importance 

 by the secondary thrombus as to be overlooked. 



The third factor, the mechanical difficulties of the distant 

 circulation, combines almost inextricably with the weakened 

 heart in i)roducing the spontaneous coagula or thrombi. It is, 

 nevertheless, clearly the principal factor in precipitating the 

 gangrene in the lower extremities. Not oi\\}\ however, are the 

 inferior parts of the body thus involved in gangrene, but the 

 frequency of venous thrombi, and the resulting phlegmasia in 

 the same region, is a strong argument in the same direction. 

 Bouchut* found in 51 cases of non-puerperal venous coagula, 

 that 44 were situated in the pelvic, femoral, or tibial veins. I 

 have memoranda of 63 cases of venous coagula following the 

 continued fevers in which the site is stated. Only two cases 

 involved the upper extremity alone, and were both followed by 

 gangrene; one involved both the arm and leg; all the other 

 60 cases were limited to the lower extremities.^ Both forms 

 of coagula — the arterial and the venous — form most frequenth", 

 during or just after the period of greatest cardiac weakness — 

 a weakness felt most at such distant points as the legs. Of 18 



' Gaz. Med. de Paris, 1845. p. 241. 



^ See a very interesting case which got well after a second attack of 

 typhus thirty years later. Stokes on Fevers, Phila., 1876, p. 249 (repub- 

 lished in Med. News and Library), 



