SECTION III, 1916 [27] TRANS. R.S.C. 
® 
A New Method for the Determination of Nicotine in Tobacco 
By ALFRED TINGLE AND ALLAN A. FERGUSON 
Presented by PROFESSOR W. R. LANG, F.R.S.C. 
(Read May Meeting, 1916.) 
INTRODUCTION 
Although it has been accepted as a standard for many years, 
Kissling’s method of determining nicotine in tobacco and tobacco 
extracts is not at all an ideal one. J. A. Emery has pointed out 
(Jour. Amer. Chem. Soc. XXVI, 1113) how completely it fails when 
applied to certain tobacco extracts and has proposed an improved 
method of his own for use in these cases. This depends in part on 
polarimetric observation. Our own experience has led us to think well 
of Emery’s method, despite the rather cavalier way in which it is 
dismissed by R. M. Chapin (U.S. Dept. of Agriculture, B.A.I. Bulletin 
133); 
Emery also tried (Joc. cit.) to determine nicotine in tobacco leaf by 
two methods. According to the first he followed Kissling’s procedure 
for the most part, but modified it by diluting the final distillate to 
500 cb.c. and measuring the rotatory power of the resultant solution. 
For reasons to be given later we do not consider this method practical. 
His second proposal turned on the steam-distillation of the tobacco 
to be examined, after mixing it with a solution of caustic alkali. 
This solution causes much trouble by frothing and bumping; Emery 
confesses to having obtained only poor results. 
Cox (Pharm. Jour. Jan. 20th, 1894), mixed tobacco with slaked 
lime, and distilled-in a current of steam. We found that this mixture 
also gave much trouble by frothing, and our experiments generally 
ended in the whole contents of the distilling flask being projected 
down the condensor. 
We have found that when barium hydroxide in large quantity is 
substituted for the caustic alkali or lime in the foregoing methods, 
all the nicotine can be distilled over in steam, and that no precautions 
against frothing are needed. The operation can be carried on as 
quietly and easily as any steam distillation we have ever performed. 
The method which we propose for determining nicotine in the 
distillate is a polarimetric one. Its accuracy therefore depends 
