242 Tobacco as a Farm Crop for England. 
combustion of the organic matter present, the substance was mixed with an 
excessive amount of copper oxide in a fine state of powder, and ground down 
in the mortar with it, then placed in the combustion tube with the copper 
roll, and burnt in the usual manner. The following are the results : — 
Percentage of Total Nitrogen. 
No. 1. No. 2. No. 3. No. 4. iNo. 5. No. 6- No. 7. 
4-62 4-16 4-67 4-65 4-33 3-52 4-24 
The total amouut of nitrogen is of no particular assistance in deciding as to 
the quality of a tobacco, but it is still of interest as showing the amount taken 
up by the plant from the soil. 
What is present in the case of the English samples appears to be all 
organic nitrogen, as the leaves were tested most carefully for nitrates, and not 
a trace could be found. This observation applies to the fleshy part of the 
leaver only, as the veins contained small traces of nitrates and the mid-rib 
considerable traces. Nitrates were found in the fleshy part of the American 
samples, however, although in very small quantities. 
The condition in whicli the nitrogen existed was not thoroughlj^ investi- 
gated, but sufiBcieut was done to cast very serious doubts on the existing 
ideas of the changes by fermentation and the causes of the combustibility of 
tobacco. This subject is being pursued, and I hope at some future date to 
refer again to it. 
The amount of soluble matter in the leaf was next determined. This was 
done by heating a weighed quantity with distilled water for one hour to a 
temperature of 80° C. on a steam bath, filtering off the solution, washing the 
residue, drying it at 100° C. and weighing it. The following figures were 
obtained : — ■ 
No. 1. 
No. 2. 
No. 3. 
No. 4. 
No. 5. 
No. 6. 
No. 7. 
Per Cent. 
Per C«!nt. 
Per Cent. 
Per Cent. 
Per Cent. 
Per Cent. 
Per Cent. 
Soluble extract . . . 
58-00 
58-64 
56-55 
57-11 
45-36 
39-70 
38-27 
42-00 
41-36 
43-45 
42-89 
54-64 
60-30 
61-73 
The results agree very well in the case of the first four samples, but the 
percentages of soluble extract are very high. It is recorded in connaction 
with foreign tobaccos that the highest extractive obtained in this way was 
not over 55-0 per cent, and the average is about 10 per cent, lower, so that 
the extractive in the above four samples is excessive and tends to confirm 
the previou.sly expressed opinion that the plants have been forced. 
The amount of ash contained in the dried leaves after extraction with 
water was next ascertained, as also the amount of nitrogen, with the following 
results : — 
Percentage of Ash and Nitrogen in the Resibue from Aqueous Extract. 
No. 1. 
No. 2. 
No. 3. 
No. 4. 
No. 6. 
No. 6. 
No. 7, 
Ash 
10-89 
413 
11-40 
3-06 
11 -71 
4-25 
11-61 
3-29 
13-22 
3-45 
18-78 
3-21 
14-44 
4-45 
