182 Scientific Intelligence—Botany. 
7. For the formation of one square mile of the depth of 1,056 
feet, one year sixteen and one-fifth days. 
8, For the formation of the Delta, according to 2, 3, 4, time re- 
quired, 14,2084 years. 
9. The valley of the Mississippi, from Cape Girardeau: to the 
Delta, is estimated to contain 16,000 square miles, of 150 feet depth ; 
it therefore contains 66,908,160,000,000 cubic feet, or 4543 cubic 
miles.—(American Annual of Scientific Discovery, 1854, p. 306.) 
12, Age of our Planet,—It is supposed that the plants of the coal 
period required a temperature of 22° Reaumur. The mean now is 
8°, or 14° less. 
By experiments on the rate of eye of lavas and melted basalt, 
it is calculated that 9,000,000 of years are required in the earth to 
lose 14° Reaumur. 
M. Hibert puts the period at 5,000,000. But supposing the whole 
to have been in a molten state, the time that must have elapsed 
in passing from a liquid to a solid state is fixed at 350,000,000 
years.—(Ami Boué.) 
13. Use of Nitrate of Soda as a Fertilizer.—The Royal (English) 
Agricultural Society having offered a prize for a manure equal to 
guano at a cost of £5a ton, Mr Pusey has shewn that the conditions 
are satisfied by nitrate of soda, and at a charge less than that specified. 
He says in illustration, that 46 acres of land, if cropped with bar- 
ley, and dressed with 17 cwt. of nitrate, would yield an increase of 
80 sacks beyond the quantity usually obtained. A cargo of this 
fertilizer was brought to England in 1820, but for want of a pur- 
chaser was thrown overboard; a second importation took place in 
1830; and from that date up to 1850, the quantity brought from 
Peru, where the supply is inexhaustible, was 239,860 tons, value 
£5,000,000. With the price reduced to £8 a ton—Mr Pusey ob- 
serves—‘“ Our farmers might obtain from their own farms the whole 
foreign supply of wheat without labour, and with but a few months’ 
outlay of capital. I do not mean to say that no failures will yet 
occur before we obtain a complete mastery over this powerful sub- 
stance; but I am confident so vast a resource of nitrogen—the 
main desideratum in the worn-out fields of Europe—cannot long be 
left within a few miles of the sea, passed almost in sight by our 
steamers, yet still nearly inaccessible, at the foot of the Andes,’’— 
(American Annual of Scientific Discovery for 1854, p. 281.) 
BOTANY, 
14. Progress of Flaw Cultivation in Ireland.—The recent in- 
crease in the growth of flax in Ireland has been extraordinary, as the 
a 
