The influence of a burning climate may be modified by choosing the coolest month of the year, whereas the soil cannot be altered without incurring great expense.  I have seen tobacco lose its natural quality and degenerate by transplanting from one soil to another, although of the same temperature, and vice versa.

Mr. Piddington has analysed several Indian soils, distinguished for the production of superior tobacco.  These are the table soils from Arracan, (Sandoway,) a soil from Singour, in Burdwan, near Chandernagore, the tobacco of which, though of the same species as that of the surrounding country, sells at the price of the Arracan sort; and the soil of the best Bengal tobacco, which is grown at, and about Hingalee, in the Kishnagur district.

The best tobacco soils of Cuba and Manila, are for the most part red soils.  Now, the red and reddish soils contain most of their iron in the state of peroxide, or the reddish brown oxide of iron; while the lighter grey soils contain it only in the state of protoxide, or the black oxide of iron.  Mr. Piddington believes the quality of the tobacco to depend mainly on the state and quantity of the iron of the soil, while it is indifferent about the lime, which is so essential to cotton.  None of the tobacco soils contain any lime.  Their analysis show them to contain:—­

Arracan soil.    Singour soil.   Hingalee soil. 
Oxide or iron, (peroxide)      15,65           10,60           6,00
Water and saline matter         1,10              75           1,50
Vegetable matter and fibre      3,75            1,10             75
Silex                          76,90           80,65          87,25
Alumina                         2,00            4,50           1,50
-------         -------        -------
99,40           97,60          97,00
Water and loss                    60            2,40           3,00
-------         -------        -------
100             100            100

From which it will be seen that the best tobacco soil hitherto found in India contains about sixteen per cent., or nearly one-sixth, of iron, which is mostly in a state of peroxide; and that the inferior sort of tobacco grows in a soil containing only six per cent., or one-sixteenth of iron, which is, moreover, mostly in the state of protoxide, or black oxide.  Mr. Piddington thought it worth examining what the quantity of iron in the different sorts of tobacco would be, and found that while the ashes of one ounce, or 480 grains of Havana and Sandoway cheroots gave exactly 1.94 grains, or 0.40 per cent., of peroxide of iron the ashes of the same quantity of the Hingalee, or best Bengal tobacco, only gave 1.50 grains, or 0.32 per cent.; and it appears to exist in the first two in a state of peroxide, and in the last as a protoxide of iron; rendering it highly probable that the flavor of the tobacco to the smoker depends on the state and quantity of the iron it contains!  Green copperas water, which is a solution of sulphate of iron, is