The Portsmouth inquirer. [volume] (Portsmouth, O. [Ohio]) 1849-1855, 1850-11-04
scientinc Facts.

Professor Johnston, in the course Of lee
lures delivered by him before the N. York
State Agricultural Society, stated the follow
ing things, worth remembering
|. In this climate the temperature rises
to 1909 Fahrenheit five feet below the sur
face, and to 400 half an inch below it,
facts, which he says he learned himself with
surprise. He uses them to illustrate the
economy Of nature in promoting vegetation.
2. The sun-beam is composed Of three dis
tinct and separate rays, one of heat, one Of
light, and one called the chemical ray.-
These three agencies exist in different pro-
portions in the sunbeam in the spring,
summer, and autumn. The blue or chem
ical ray is greater in the spring; the light
greater in the summer. The chemical ray
is less in autumn and then the heating ray
'pfedominates. The proportions Of these
rays vary in different seasons of the year in
order that the growing plant may arrive at
maturity. 1t has also been ascertained that
the proportions of these agents vary in diff
ferent climates.
3. II has been ascertained that the flower
OF plant absorbs more heat that the other
parts, and the dark more than the light and
hence it is inferred that the color Of flower
is what determines the quantity Of heat it
requires, and the amount which nature sup
plies.
a. Drainage is as necessary in dry and
sandy, as in wet soils. "If soil is merely
burnt up by 6lought, and you suppose the
roots to descend only to the depth OF about
three inches, it is obvious that the heat OF
the summer dries up the land 10 the roots
But if by drainage you open up the soil
three feet deep, SO that the rain, instead OF
flowing off the surface, descends through the
soil thus made previous to il, the roots will
grow deeper, and while the upper surface is
dry, the drought does not reach the roots,
which are thus enabled to live longer than
they otherwise would"
5. Tobacco is acrop which contains much
mineral matter. Suppose an acre to yield
800 lbs, these 800 lbs. will contain about
l60 lbs, Of mineral matter, which is carried
off by the crop, and in this way the land will
soon be exhausted. In four years, 600 lbs
Of mineral matter would be carried off from
an acre of tobacco land. II lis the duty o
the farmer TO supply the mineral matter
thus specially exhausted, ifhe wishes to sus.
tain the soil.
6. There are certain parts Of every portion
of every animal removed every day; and a
quantity Of new material put in its place.
Hence the animal should have a constant
supply, in order that this daily waste may
be made up. An animal requires, to sus-
tain its body in good condition, or to supply
what is called the sustaining food, about one
sixtieth part Of itsown weight daily. If you
wish to increase its size, or enable il to
work, you must give it more. If you feed
for milk, twice the quantity.
Z. 1t will be found that the soil and the
plant contain nearly the same substances,
the only one not in The plant being Alumina.
The mechanical function of alumina in the
soil is to anchor the plant. Its tenacity is
its available property. Some plants grow in
mere sand, but the great majority OF them
require certain degree of tenacity in the
soil, which is obtained by mixing silica with
clay. This alumina does not enter into
the plant, but only gives to the soil the te.
nacity necessary 10 retain the plant.