56 
to 75° C. (167° F.). By this control test erroneous conclusions can 
be avoided. ; 
An accumulation of nitrites in the sweating tobacco might in the 
course of some weeks attack the oxidizing enzyms at the temperature of 
the fermenting heaps, thus terminating this process sooner than desir- 
able. Hence nitrates should not be applied in too large quantities in 
the manuring of tobacco fields, since they may give rise to the forma- 
tion of nitrites in the sweating process. Bacterial action need not be 
assumed in this process. 
AMOUNT OF HEAT PRODUCED BY SWEATING IN BULK. 
Since the loss of organic substance from the cured leaves in the sweat- 
ing in bulk amounts to about 5 per cent dry matter, and the cured 
leaves consist of nearly 40 per cent of carbon and 6 per cent of hydro- 
gen, al approximate calculation can be made as to the amount of heat 
generated by the oxidization going on in the heap. For an accurate 
calculation it would be necessary to know the exact amount of carbonic 
acid and water formed by the oxidation, and further, how much of the 
carbonic acid was generated from previously present carboxyl groups, 
and how much water was generated from previously present hydroxyl 
groups; moreover, it should be known how much total ammonia is 
produced in the sweat. But, on the assumption that only one-half of the 
carbonic acid and one-half of the water produced are due to perfect 
combustion, and that the carbon and the hydrogen in these products show 
the same proportion as in the cured tobacco, we will obtain numbers 
which are certainly rather an underestimation than otherwise. The 
fermenting piles are made up of from 2,000 to 7,000 kilograms of 
tobacco. Let us assume a pile with 2,000 kilograms of dry matter. 
The 5 per cent loss after the sweat would then amount to 100 kilo- 
grams. According to our assumption this would involve a complete 
combustion of 20 kilograms of carbon and 3 kilograms of hydrogen. 
Since one gram of carbon produces 7,678 units of heat and one gram of 
hydrogen 35,808 units of heat, it follows that 20 kilograms of carbon 
would yield 153,560 major calories and 3 kilograms of hydrogen 101,400 
major calories. This heat would suffice to heat up 254,960 liters of 
water for 1° C. 
CONCLUSION. 3 
Various problems relating to the manufacture of tobacco have been 
touched upon in this report, some of them within easy reach of 
Solution, others of a very difficult nature. The prevention of fungous 
attacks in the barn or in the cases, the regulation of the temperature 
and humidity in the curing process, and the proper control of the 
Sweat are points that can easily be settled. In many cases the re- 
placement of the stalk-curing by the single-leaf curing process may 
prove a financial success. But there are other problems of a more 
