264 TOBACCO PRODUCTION IN THE UNITED STATES. 



grow fluer and make a really superior quality of tobacco upon sanely soils, fashion has dictated that darker colors 

 are most desirable for cigar wrappers, and the colors most in demand are grown upon argillaceous and calcareous 

 loams. The fine yellow types of North Carolina and Virginia are grown upon light-colored arenaceous soils. 



Tobacco culture, perhaps more conspicuously than any other kind of farming, exhibits the condition of 

 agricultural progress in the regions in which the staple is produced. The revenue tax has had the effect of 

 discriminating in favor of good tobacco, has really been an incentive to the production of finer types and 

 better grades, and has induced better cultivation and more careful management. Progressive enterprise in 

 tobacco growing has had most beneficial effects upon other agricultural pursuits. The tobacco-field usually 

 occupies but a few acres upon the farm, and in most cases gets a large share, if not all, of the manures saved at 

 home. It is upon these limited areas, in all parts of the country, that the most carefully-conducted and best 

 authenticated experiments have been made with commercial fertilizers. Wherever tobacco culture has been made 

 profitable, there has been an increase of all farm products suited to the locality. 



In the preparation of these reports the object has been to furnish abundant information as to the geological 

 position, the lithological constitution, and the geographical location of all soils which have been found specially 

 adapted to certain classes and types of tobacco. 



CHAPTER XXI. 



REPORT ON THE CHEMISTRY OF AMERICAN TOBACCOS, BY GIDEON E. 



MOORE, PH. D. 



Tobacco in commercial form represents the products of vegetable growth more or less changed by fermentative 

 or putrefactive processes. The peculiarities of the different varieties are, therefore, of twofold origin, being due, 

 first, to the diverse conditions of soil, climate, and mode of cultivation ; and, second, to the effects of the processes 

 of curing to which the harvested leaf has been subjected. While, therefore, it is permissible to trace out the 

 relations between the nature and the relative amounts of the constituents of the finished commercial product and 

 the properties upon which the technical application and commercial rank of the latter depend, the question of the 

 influence of the diverse conditions, under which the cultivation of the different varieties has been effected, on the 

 quality of the finished product, can only be decided from the results of the chemical examination when due regard 

 is had to the modifying effects on the composition of the product, exerted by the processes of curing to which it has 

 been subjected. These last consist either in simply drying the leaf by exposure either to the heat of the sun or 

 to more or less carefully regulated artificial heat, in which case fermentative change is either avoided or reduced 

 to a minimum ; or they consist in a more or less perfect fermentation preliminary to, or simultaneous with, the 

 operation of drying, and in this case result in essential modifications in the composition of the leaf and degree of 

 adaptability to the different applications for which it is designed. The process of curing, however conducted, is 

 only then regarded as complete and the tobacco fit for market after the leaf has undergone a supplemental 

 process of fermentation, technically known as "sweating". This sweating occurs during the spring or summer 

 following the curing propeV. It is attended with elevation of temperature to 120 P., and results in essential 

 modifications in the flavor and combustibility of the tobacco, and necessarily also in its chemical composition. 



CONSTITUENTS OF THE TOBACCO LEAF. 



The constituents hitherto detected in the leaf of the tobacco plant are as follows, viz : 



NICOTINE (CioH 14 N 2 ). A volatile oily substance, possessing a strong, acrid, tobacco odor. It is a powerful 

 base, and forms well characterized compounds (salts), with the stronger acids. It is to this substance that the 

 narcotic and toxical properties of tobacco are chiefly to be ascribed, especially when the leaf is chewed or the 

 decoction is administered internally. When the tobacco is smoked, the nicotine is partly decomposed, and its 

 decomposition products, together with those of the other constituents of the leaf, co-operate with the nicotine that 

 sublimes unaltered to produce the physiological effects of the smoke. 



Nicotine is present at a very early stage in the development of the tobacco plant. According to Nessler (Der 

 Tabak, seine Bestandtheile und seine Beliandlung : Mannheim, 1867, p. 12) it is present in the ribs and parenchyma 

 of the leaves of the young plant when the leaves are only 1 to 2 inches long. The following determinations by 

 Nessler show the proportions present in leaves of different degrees of maturity : 



Percentage of Percentage of 

 nicotine in the nicotine m the 

 fresksubstance. dry substance. 



1. Ribs of leaves 2 to 2 inches in length 0.164 1. 63fi 



2. Parenchyma of leaves '2 to 2| inches in length 0.379 2.840 



3. Parenchyma of leaves 10^ inches wide and 1(! inches long 0.660 5.680 



4. Parenchyma of leaves 3J inches wide and 8^ inches long 0. S25 1. 495 



858 



