34 THE TONER LECTURES. 



determining influence. Of 81 cases, 56 were males and 25 

 females. This is the more curious when we consider that the 

 number of deaths in men, and therefore presumably of cases, 

 does not hold at all the same relation. In 1868, in Finland, 

 31,000 males and 28,000 females died; yet of 31 cases of 

 gangrene of the legs, 25 were males, and only 6 females. The 

 site of the gangrene is very suggestive also. In 5 cases it was 

 in the ears, 10 in the nose, 27 in the face, neck, and trunk, 5 in 

 the arms, 1 in the genitals, and 72 in the legs; that is, of 126 

 localities, in 77 it was in the extremities, and in 22 more, in 

 other peripheral districts of tiie vascular system (ears, nose, 

 genitals). 



As far as the pathology of the cases is concerned, they may 

 be divided into two classes: 1, those with a discoverable clot; 

 and 2, tliose Avithout such a clot. Murchison believes that all 

 cases of spontaneous gangrene arise from arterial thrombosis, 

 but the careful post-mortem examinations of Estlander and 

 others show, that at least in the larger visible vessels, sometimes 

 no such thrombus exists. 



1. Those with clot. The cause of sneh clots, as Humphrey^ 

 and others have shown, is not the condition of the bloodvessels. 

 But seldom have I found it stated, that the arterial walls were 

 diseased ; and when tliey were, it was presumably a secondary 

 process, the result, and not the cause of the clot. Few, if 

 any, pathologists will now attribute such results, with Bour- 

 geois, to a metastasis, especially when arising in convalescence, 

 as these so frequently do. Gigon has attributed them to chemi- 

 cal alterations in the blood, which give it an irritative character, 

 and this, with friction at points of curvature, produces inflam- 

 mation and coagulation. If so, a fair proportion of cases 

 should be seen in the upper extremities, where the same irri- 

 tating blood circulates and similar curves exist. How rare 

 tills is, we have alread}' seen. 



' Brit. Med. Journ., 1859, p. 582. 



