46 THE TONER LECTURES. 



The alternation of the two is the condition of health, and its 

 artificial production will tend to restore healthful reaction. 



Chapman's ice and hot-water bags to the spine, alternate 

 heat and cold directly to the parts, with proper friction and 

 stimulating liniments, at once commend themselves, to us. 

 The constant current battery also may prove an extremely 

 useful aid, since it dilates the deep as well as the superficial 

 vessels, and will aid the collateral circulation. 



But suppose gangrene actually occurs, what then ? Est- 

 lander gives most judicious counsel here. We must remember 

 that good results follow both to life and limb loithout opera- 

 tion, especially if the gangrene be limited and the patient not 

 too exhausted. "We must not, therefore, be rash in our inter- 

 ference. If amputation has to be done, the question as to 

 where it should be done, depends on the probable extent of 

 the gangrene ; as to when, on the line of demarcation. In the 

 non-thrombotic cases, as the line of demarcation is usually 

 established within two or three weeks, and the disease is not 

 then likely to be progressive, the amputation may be done but 

 little above or even through it. It is, therefore, usually best 

 to wait for its formation. In the thrombotic cases, the clot and 

 the gangrene are apt to be progressive. Until the line of 

 demarcation forms, therefore, it is impossible to say precisely 

 where the disease will stop. Yet we can gain some idea of the 

 probabilities of the case from past experience. 



If the clot extend no further than the popliteal, the limb 

 may escape gangrene altogether, and if it follow, I have found 

 it limited in 9 cases, to the foot 4 times and to the upper calf 

 in 5 ; if the clot extend into the femoral, I find the gangrene 

 extended to the upper calf in 6 and to the thigh in 4 ; if the 

 clot extend above Poupart's ligament, I find in 10 cases it was 

 limited to the foot in one, the calf in 3, and extended above the 

 knee in 6. ' The results of amputation are good, giving 21 

 recoveries to 21 deaths, but the recoveries are largely after 



