Dr. I. C. Bloodgood (Boston Medical and 
Surgical Journal, No. 2, 1914), who has ex- 
amined 200 cases of lip cancer says that smok- 
ing is a common factor, the disease when occur- 
ing being usually on the site of a neglected and 
ulcerated smoker’s burn. The burn may be a 
charring of the skin due to a very hot pipe stem 
or burning cigar stem. He says, moreover, 
‘that if the burn is not continued and there is no 
other injury, this defect may heal without evi- 
dence of ulceration. 
Similarly a cancer may be the result of con- 
tinual use of a broken or rough pipe stem or 
from using a pirty pipe stem on a broken skin. 
All these are clearly matters which the average 
smoker easily and usually avoids. It is, how- 
ever, clear that tobacco itself is in no way 
responsible for cancer, and no responsible 
medical writer on the subject alleges that it is. 
Most of the medical writers who have in- 
scribed injurious physical effects on the nerv- 
ous system, heart and sense organs, to excessive 
tobacco smoking have stated that these effects 
are due to the toxic action of the alkaloid 
nicotine known to exist in tobacco. There is 
a wide difference, however, in the results ob- 
tained by different writers as to the amount of 
the nicotine in tobacco which finds its way with 
the tobacco smoke. Moreover, some of the in- 
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