It is among the inscrutable dispensations of Providence, that the
arts most useful to man, have been of later discovery--of slower
growth, and of less marked improvement, than those that aimed only
at his destruction.--At a time, when the phalanx and the legions
were invented and perfected, and when the instruments they employed
were various and powerful, those of agriculture continued to be few,
and simple, and inefficient.
Of the Greek plough, we know nothing; and the general disuse of that
described by Virgil and Pliny, furnishes a degree of evidence, that
experience has found it incompetent to its objects.--With even the
boasted lights of modern knowledge, scientific men are not agreed
upon the form and proportion, most proper for this instrument. As
in other cases, so in this, there may be no _abstract perfection_;
what is best in one description of soil, may not be so in another;
yet, as in all soils, the office of the plough is the same, viz.
to _cleave_ and _turn over the earth_, there cannot but be some
definite shape and proportions, better fitted for these purposes,
and at the same time less susceptible of resistance, than any other.
This beau ideal, this suppositious excellence, in the mechanism of a
plough, has been the object of great national, as well as individual
research. In Great Britain, high prizes have been established for
its attainment; and in France, under the ministry of Chaptal,
10,000 francs, or $2000, were offered for this object, by the
agricultural society of the Seine. In both countries, the subject
has employed many able pens; those of Lord Kaimes, of Mr. Young,
of Mr. Arbuthnot, of Lord Somerville, and of Messieurs Duhamel,
Chateauvieux, Bosc, Guillaume, &c. It is not for us, therefore, to
do more than assemble and present such rules for the construction of
this instrument, as have most attained the authority of maxims.
1st. The beam, or that part of the plough which carries the
coulter, and furnishes the point of draft, should be as near that
of resistance as possible; because the more these are approached,
the less is the moving power required. Even the shape of the beam is
not a matter of indifference. In the old ploughs, it was generally
straight, but a small curve is now preferred; because it has the
effect of strengthening the coulter, by shortening it.
2d. The _head_ of the plough, is the plain on which it moves.
This should be concave, because that form offers fewer points of
friction, and, of course, less resistance. Between the beam and the
head, is an angle, on which depends the principal office of the
plough; the making, at will, a deep or a shallow furrow. If you wish
a deep furrow, diminish the angle, and vice versa: but this angle
should, in no case, exceed from 18 to 24 degrees.
The resistance made to the plough being produced less by the weight
of the earth, than by the cohesion of its parts, it is evident,
that the head should be shod with iron, and rendered as smooth as
possible. This remark applies equally to the soc and to the mould
board.
3d. The soc, in its widest part, should be larger than the head.
It has different shapes in different countries. In some is given
to it that of an isosceles triangle; in others, that of the head
of a lance; in Biscay, that of a crescent; and in Poland, of a two
pronged fork. But, whatever be its shape, it should be well pointed
and polished--enter the earth with facility, and cut it easily.
4th. To the _mould board_, some workmen give the shape of a
prismatic wedge; others make the upper part convex, and the lower
concave; while many make it entirely flat. In stiff soils, the _semi
cycloid_ is the form to be preferred, and in loose friable soils
the _semi-ellipsis_.[7] The iron mould boards have great advantages
over the wooden, particularly when they, the shear and the soc, form
one piece, as in the plough of Mr. Cook.
[7] See Arbuthnot on Ploughs.
It is a general opinion, that a heavy plough is more disadvantageous
than a light one; because the draft of the former, being greater,
will be more fatiguing to the cattle: but the experiments of the
agricultural society in London, establish a contrary doctrine, and
show, that in light grounds, the labour is more easily and better
performed, with a heavy, than with a light plough.
5th. The _coulter_ is a species of knife inserted in the beam, and
so placed before the soc, as to cut the sod. It is susceptible of
being raised or depressed at will.
6th. The handles of the plough ought to be made of some kind of
heavy wood, that they may operate as a counter-weight to the head,
the soc and the mould-board.
To these remarks we subjoin two sets of experiments made with
the most approved French and English ploughs; that of Guillaume,
and Small's _Rotheram plough improved_, which furnish a means of
comparison between the best ploughs of Europe and those of this
country.
The resistance (stated in these tables) was measured and ascertained
by a _dynonometer_, a machine, indispensable to those who would make
correct observations on the relative advantages of different ploughs.
_The French Plough._ _The English Plough._
Resistance in pounds. Resistance in pounds.
1st experiment 200 1st experiment 360
2d do. 240 2d do. 380
3d do. 200 3d do. 480
4th do. 220 4th do. 460
5th do. 220 5th do. 400
---- 6th do. 400
Divided by 5)1080 7th do. 420
---- 8th do. 386
Average, 216 9th do. 440
----
Divided by 9)3720
----
Average, 413
II. _The Harrow._ This is of different kinds--the triangular and
the square, the single and the double. But of whatever form, its
uses are the same; to smooth the field after ploughing, to break and
pulverize the clods, and to cover the seed.--These uses sufficiently
indicate the propriety of employing two in succession; one of
heavy frame, with few and long teeth, like the Scotch brake; the
other, of lighter constitution, with more and shorter teeth. Our
own experience leads us to believe, that the common harrow covers
the seed too much, because small seeds will not vegetate at a depth
greater than three inches.
III. _The Roller_ is a cylinder of heavy wood, turning on gudgeons,
or on an axle, and placed in a frame, to which is attached a shaft;
it is of different dimensions, but need not exceed that which may
be drawn by one, or at most by two horses or oxen. This instrument
is indispensable in good husbandry, yet is rarely used in ours.
Its offices are three-fold--to render loose soils more compact; to
break the clod on stiff ones, and on both, to compress the earth,
(after seeding) so that it be every where brought in contact with
the grain. It is also usefully employed in reinstating the roots of
meadow grasses, loosened and raised by the alternate freezing and
thawing of the ground, and, with similar view, may be passed over
winter crops early in the spring.
Its clod-breaking and pulverizing property is much increased, by
surrounding the roller with narrow bands of iron, two inches broad,
three inches thick, and six inches asunder; or by studding it with
iron points, resembling harrow teeth, and projecting three or four
inches.
IV. _The Threshing Machine_ is of English invention, and may be well
enough adapted to the taste and circumstances of rich amateurs, but
not at all to those of farmers in general. Our objections to it
are three--the first cost, which is great; the quantum of moving
power employed, which is equal to that of six horses, and the number
of hands required to attend it, which is not less than four. We
have seen, in France, a machine for the same purpose, but of much
simpler structure--called the "_Rouleau de depiquer_" which is only
a _fluted cylinder_; yet simple and cheap as this was, it could not
maintain itself against the more ancient instruments--the flail and
the horse. Still it is to be hoped, that new experiments may succeed
better and abridge the manual labour usually given to this branch of
husbandry, and, that the mechanical genius of our own country (which
is not inferior to that of any other) may be the first to combine
_power_ and _cheapness_ in this machine.
This hope is probably suggested, by the description of a new
invented threshing machine, now before me, and which I may be
permitted to transcribe from the letter of the inventor. "The
machine I have built, is three feet wide. One horse will thresh
with much ease, as much wheat as can be laid on it, by one man,
(the straw to be taken away by another,) say, from _fifty_ to _one
hundred bushels in a day_, and the saving of grain will pay for the
labour; for, I think, that with good attendance, not a particle of
grain can escape with the straw.--The expense of the machine will be
from _fifty_ to _seventy dollars_, exclusive of the moving power,
which is a wheel, about ten feet diameter, on an upright shaft, to
which a lever is fixed to hitch the horse. Into this main wheel,
a small one should be made to work, about two feet diameter, on a
shaft carrying a drum, four feet wide. With this simple gearing,
and drawn by a horse that walks well, the machine will give about
eighteen hundred strokes in a minute, and if fully attended, will,
without hard labour for the horse, thresh a _bushel every three_ or
_four minutes_. It stands in my barn, and may be seen and examined
by any one."[8]
[8] Mr. Levi M'Keen, of Poughkeepsie.
V. _The Fanning Mill_. Other things being equal, the cleanest wheat
is most easily preserved, and, on manufacture, gives the best flour,
and in the largest quantity. These considerations offer inducement
enough for the employment of this machine, which, however, besides
doing its business well, saves a great deal of time. It is too well
known to require description.
ON BONES, &c. AS MANURE.
The carbon and hydrogen abounding in oily substances fully account
for their effects; and their durability is explained from the
gradual manner in which they change by the action of air and water.
_Bones_ are much used as a manure in the neighbourhood of
London.--After being broken and boiled for grease, they are sold to
the farmer. The more divided they are, the more powerful are their
effects. The expense of grinding them in a mill would probably be
repaid by the increase of their fertilizing powers; and in the state
of powder they might be used in the drill husbandry, and delivered
with the seed in the same manner as rape cake.
Bone dust, and bone shavings, the refuse of the turning manufacture,
may be advantageously employed in the same way.
The basis of bone is constituted by earthy salts, principally
phosphate of lime, with some carbonate of lime and phosphate of
magnesia; the easily decomposed substances in bone are fat, gelatine
and cartilage, which seems of the same nature as coagulated albumen.
According to the analysis of Fourcroy and Vauquelin ox bones are
composed
Of decomposable animal matter, 51
phosphate of lime, 37.7
carbonate of lime, 10
phosphate of magnesia, 1.3
-----
100.
-----
M. Merat Guillot has given the following estimate of the composition
of the bones of different animals.
Phosphate of lime. Carbonate of lime.
Bone of Calf, 54
Horse, 67.5 1.25
Sheep, 70 5
Elk, 90 1
Hog, 52 1
Hare, 85 1
Pullet, 72 1.5
Pike, 64 1
Carp, 45 5
Horses' Teeth, 85.5 25
Ivory, 64 1
Hartshorn, 27 1
---- ----
The remaining parts of the 100 must be considered as decomposable
animal matter.
_Horn_ is a still more powerful manure than bone, as it contains a
larger quantity of decomposable animal matter. From 500 grains of
ox-horn, Mr. Hatchett obtained only 1-5 grains of earthy residuum,
and not quite half of this was phosphate of lime. The shaving or
turnings of horn form an excellent manure, though they are not
sufficiently abundant to be in common use. The animal matter in them
seems to be of the nature of coagulated albumen, and it is slowly
rendered soluble by the action of water. The earthy matter in horn
and still more that in bones, prevents the too rapid decomposition
of the animal matter, and renders it very durable in its effects.
--[_Davy's Ag. Chem._