DRILLING, in husbandry, a method of sowing grain or seed of any kind, so that it may be deposited in the ground at an uniform depth; a circumstance of the utmost importance, to the production of healthy and vigorous plants.
This method differs from the old, or broad-cast husbandry, which is performed by sowing the grain, or seed, with the hand; whereas the new practice is effected by one of the most useful machines ever invented, and called a drill-plough. It was originally introduced into this country about sixty years since, and at first violently opposed as an useless innovation, till it was proved, by repeated experiments, to be indisputably the best mode of sowing hitherto contrived.—See Broad-cast, vol. i. p. 359.
By the broad-cast system of culture, the land is often sown in bad tilth, the seed is always scattered at random, and sometimes by very unskilful hands. In drilling, the ground must be in good order; and the seed set in trenches regularly drawn, all being nearly of an equal depth, which is adapted to the nature of each particular kind of seed. These seeds are also distributed at proper distances: and, by being equally and speedily covered, are most effectually protected from vermin, and other accidental injury. Farther, in consequence of the broad-cast practice, the seed falls in many places too thick, in others too thin; and, being imperfectly covered, part of it is devoured by vermin which follow the sower; the remainder is exposed to rain or frost, or to heats, either of which are very hurtful. When harrowed in, a considerable portion of the seed is so deeply buried in the soil, that if the latter be wet, it putrifies before it can vegetate.
Besides, when corn is thus sown, the crop will not admit of being touched afterwards, because its growth is irregular. The soil cannot be broken in order to afford it more nourishment; nor can even the weeds be destroyed without much damage and inconvenience. On the contrary, in the drill-husbandry, the intervals between the rows, whether double or single, may be horse-hoed; and nourishment may thus he repeatedly given to the plants, and the weeds almost totally extirpated. Drilling, however, is not calculated for every soil; yet as there are but few situations, in which the broad-cast method is preferable to it, they ought not by any means to impede the more general introduction of the former.
The drill-husbandry is said to be attended with many disadvantages: namely, 1. That it is very difficult to procure persons who are acquainted with the use of the drill-plough, or its proper management, when on the soil. 2. That the earth requires to be well prepared to admit of it. 3. That the crop is too thinly sown by it. 4. That drilled-crops are harvested later than broad-cast ones. 5. That clover does not succeed, when cultivated according to the drill-husbandry. 6. That oats produce rank and coarse straw, which does not afford wholesome food for cattle.
These objections appear formidable, and it must be allowed, that no person can acquire a thorough knowledge of the drill-husbandry in one season. It is nevertheless untrue, that the seed is too thinly sown; for, though the quantity required is nearly one half less (which is consequently saved), yet the crops of drilled wheat are, in general, so much more valuable than those of broad-cast, whether we consider the quantity, quality, or weight of the grain, that the inferiority of the latter is evident to every impartial observer. This reason is likewise a sufficient answer to the objection alledged against the expence of horse-hoeing, which eradicates almost every weed, even where hand-hoeing is impracticable; and consequently in a very considerable degree promotes vegetation.
To this we may add, that by drilling, the seed grows more regularly and vigorously; and that though the crops are harvested later than broad-east ones, yet they are gotten in in with less expence, and with greater safety, while the soil is left in a better state for future crops.
Such are the advantages and disadvantages attending the drill-husbandry, which we have endeavoured fairly to state: after these decisive proofs, no rational agriculturist will hesitate to pronounce in favour of the new system.
That useful instrument the drill-plough, was first introduced in this country by the ingenious Jethro Tull, in the beginning of the last century. Since that period, various other machines, or drill-ploughs, have been invented by different persons, of which we shall mention the principal.
One of the earliest implements of this description is the hand-drill, which is chiefly employed in the low-lands of Scotland, where it was also invented. It is pushed along by two handles, in a manner similar to wheel-barrows, and sows one row at a time. The principal part of this machine is a wheel, about 22 inches in diameter, and made of solid deal, upun the axle of which is fixed a notched roller 234 inches in diameter, and 2 inches long, that turns in the fore-part of the drill-box. The quantity of seed intended to be sown, is regulated by a slider, which moves up and down in the fore-part of the box, bv an adjusting screw fixed at the top; and has a strong brush, that projects from its lower end, and sweeps upon the notched roller. There is also a sluice, or slider, which lies flat on the bottom, on the inside of the drill-box, and juts out between the two handles of the drill, so as to be within the reach of the person guiding it; who, by pushing the slide forwards, completely covers the notched roller, and prevents any of the seed from being scattered, while the drill is turning at the end of the ridges. With this implement, a woman, or boy, is able to drill from 2 to 212 acres in a day; the rows being at the distance of 20 inches.
The next contrivance is that of the ingenious Mr. Arthur Young, whose indefatigable labours in promoting agriculture, are too well known to require our encomium. In the common drill-ploughs, there are generally two or three barrels, with corresponding hoppers, or receptacles for seed, through which it is committed to the ground. Such an arrangement renders them necessarily complex; and to obviate the defect resulting from it, Mr. Young has two divisions in the barrel, and two corresponding ones in the hopper, which are more pimple, and doubtless preferable to moveable boards. In his drill-plough the whole machinery is fixed, yet he sows with it single rows at any distance, double ones at two feet, or three rows at one foot; relinquishing the other powers of mechanism, to render the plough in all its parts stronger, and more steady. It is likewise calculated for the stiffest soil; and Mr. Young adds, that it will even deposit seed in drills cut through a clay field, without any previous ploughing. For a more detailed account of this excellent machine, we refer our readers to the 3d vol. of "Annals of Agriculture," p. 240, where it is fully described, and illustrated with an engraving. The expence of this implement, when complete, is about geyen guineas and a half, if made of iron; if of wood, it may be estimated at four.
The next we shall describe, is the celebrated drill-plough invented by the Rev. James Cooke, late of Heaton Norris, near Manchester, but now of Red Lion-square, London; for which he obtained a patent in, or prior to, the year 1784. Mr. C. has since made several improvements in, and additions to his machinery; in consequence of which a new patent was granted to him, about the year 1788.
Description of the Rev. Jas. Cooke's Patent Drill Machine simplified and improved, so that it may be converted into a Horse Hoe.
(With a Copy of an accurate Engraving, approved of by the Author).
Fig. 1. A, A, are the shafts of the machine, applied to the axis of the wheels, so that the horse may walk in the furrow, without treading on the land, either for the purpose of drilling or horse-hoeing.
B, B, the wheels.
C, C, coulter-beam, with holes or mortices for the coulters, at different distances.
D, D, handles of the machine, applied to the coulter-beam, and also to the axis of the wheels, by hooks and eyes, or staples.
E, E, the upper seed-box, in partitions, covered by a lid, to protect the grain from wind or rain.
F, F, lower seed-box, in partitions.
G, G, slides between the upper and lower seed-boxes, for regulating the quantity of seed sown.
H, H, a cylinder with cups or ladles of different sizes, for various sorts of grain or seed, by which the latter are taken up and dropped into the funnels I, I, and conducted 
Rev. J. Cooke's Drill Machinery.
through these into the incisions or drills, made in the land by the coulters K, K.
L, a hook affixed to the axis of the wheels; l, a chain applied to the coulter-beam, the last link of which, when put upon the lowest hook, will prevent the tubes of the funnels from being displaced; while the machine is crossing deep furrows or gutters.
M, an iron pin, projecting from the coulter-beam, which being lifted on the hook L, at the end of the land, will bear the coulters out of the ground, while the machine is turning round, or on any other occasion, without additional labour to the person who attends the plough.
N, a cog-wheel.
O, another cog-wheel, turned by the wheel N.
P, a lever and string, passing over a pulley to the axis of the cylinder H:—by moving the lever P, to the notch in the staple Q, the wheel O, will be prevented from acting with the wheel N; so that the distribution of grain or seed may be stopped at pleasure.
R, an iron bar, perforated with holes, by means of which, and of a pin passing through the holes, the seed-box may be raised or lowered, so as to keep the lid of the box horizontal, whether the machine be ascending or descending steep hills, or moving on level ground.
S, S, two staples in the ends of the seed-box, for the reception of two slips of wood, with canvas to prevent the wind from dispersing the grain or seed: and also to prevent dirt or soil from falling off the wheels into the funnels I, I.
patent horse-hoe.
Fig. 2, (see the plate) represents the shafts, the axis, and wheels: the coulter-beam with handles, &c. as in Fig. 1; being part of the same machinery, and convertible into an horse-hoe, with 6 shares, by taking away the seed-box E, E, the cylinder H, H, the funnels I, I, the coulters K, K, as in Fig. 1, and substituting the hoes A, A, A, A, A, A, Fig. 2, for the coulters.
hand-hoe.
Fig. 3, A, is the hoe-plate or share of different sizes, for drills at different distances.
B, the wings for earthing up the soil to the rows of corn; and which may be occasionally taken off.
C, the handle.
D, a wedge, applied to the upper or under side of the handle C, so as to raise, or reduce it, according to the height of the person using it.
Fig. 4, a rake that may be applied to the handles of the machine instead of the coulter-beam, and may be used for making hay, clearing land from dog's-grass, or couch-grass, and for other purposes.
Directions for using the machine: The practice of drilling, says Mr. Cooke, should not be attempted, unless the soil be so dry, as not to adhere to the feet,—except it be to regain a late or lost seed-time. If the soil abound with large dry clods, these should be reduced by a heayy roller. Previously to being drilled, the land ought to be ploughed deep, and lightly harrowed, to render the level.
When the horse is put in the shafts, care should be taken that the chains by which he draws, be of equal lengths; otherwise the machine will deviate from the direction, in which the animal advances. In going to, or returning from the field, the pin or guide M, must be lifted on the hook L, which will bear the coulters off the ground. And, when passing through rough roads, if the coulter-beam C, C, and the axis of the wheels, be lashed together by a rope or chain, it will prevent the coulter from receiving any injury, by reaching the ground suddenly.
The cylinder H, H, is furnished with cups or ladles of four different sizes, for various kinds of grain or seeds, which are distinguished by the numbers 1, 2, 3, 4.—No. 1, (the smallest size painted white) is calculated for rape, lucerne, cole-seed, clover, &c. and will sow 2lbs. per acre. It will also sow turnip, after the rate of one pound per acre; every other cup being closed with a small quantity of soft clay. No. 2, (painted red) for wheat, and will sow one bushel per acre.—No. 3, (painted green) for barley; and will sow from 1 to 112 bushel per acre.—No. 4, (painted yellow) for peas, beans, oats, vetches, &c. and will sow two bushels per acre. Although the above quantities of grain or seed are specified, they may be increased or diminished by raising or lowering the slides (G, G, Fig. 1) at pleasure.
The funnels are applied to their respective places by numbers 1, 2, 3, 4, 5, 6; and, for drilling at nine inches, they ought to correspond with the numbers 1, 2, 3, 4, 5, 6, of the seed-box; six coulters being fixed in the beam, at the distance of nine inches from each other. For drilling 12 inches apart, five coulters should be fixed in the beam, 1114 inches distant from each other, when the order of the funnels will stand 1, 4, 5, 2, 3, 6, and no seed will be put in the box opposite the funnel No. 5, when placed as above: the unemployed funnel may be stopped with paper, to receive any seed dropping into it accidentally. In a similar manner, Mr. Cooke's machine may be so regulated as to deposit grain or seed in drills at 18 or 22 inches apart, or at any other distance.
If the coulters should not make the incisions or drills deeper than two inches in light sands or loams, or less than two in strong clays or wet soils, they may be forced into the ground by the hand, or by weights, or a beam of wood 4 feet long, and three or four inches thick, being suspended by chains or cords at the hooks T, T, in the handles of the machine, for that purpose.
In attempting to render the drills strait, if the horse should deviate from his proper course, the coulter-beam and coulters may be easily removed in any direction, in order to remedy that irregularity. In different parts of the kingdom, the lands or ridges are of various sizes: where the machine is too wide for them, one or more funnels may be stopped with loose paper, and the seed received into such funnel, returned into the upper seed-box. In drilling narrow high-ridged lands, the outside coulters may be lowered, and the middle ones raised, so that the points of the coulters may form a curve similar to that formed by the ridge. When shut, the top of the seed-box should always be kept horizontally level: thus, the distribution of the seed will be uniform. The higher the front edge of the box is raised upon the bar R, the more copiously will the seed descend into the lower boxes; and consequently a greater quantity be distributed.
No wheat should be deposited more than 112 or 2 inches deep in strong clays, or wet soils, nor less than 2 inches deep in all dry lands. Those which are intended to be drilled with carrot-seed, should be deeply ploughed; and for every half acre of land, one bushel of saw-dust and one of carrot-seed should be provided: the former ought to be well dried and sifted, in order to take out all the lumps and chips, and divided into eight equal parts. The carrot-seed should likewise be well dried, and rubbed between the hands, to take off the bears, so that it may readily separate. It must then be divided into a similar number of heaps or parcels: each of these is to be gradually mingled, till the whole of the seed and dust are thoroughly incorporated; in which state it may be regularly sown in drills, by the cups or ladles No. 2. One of these cups, when filled with saw-dust, will, upon an average, contain three or four carrot-seeds, by which means the whole of the latter will be distributed with the same regularity as any other grain or seed. If the wind should blow violently, so as to render it difficult to proceed in sowing the grain, that inconvenience may be obviated, by fixing a screen of matting or of canvas before the seed-box, which, together with the side wings (S, S, Fig. 1), will perfectly shelter the seed from wind or rain.
Directions for using the Horse-hoe.—Having already explained the construction, we shall briefly state a few circumstances relative to the management of this instrument.
In order to hoe a crop of any kind that is drilled at the distance of 9 inches, the horse ought to be conducted along the third row, or drill, computing the rows from the left side of the rows, drilled at one operation of the machine. The person who attends the hoe, should carefully keep the pin (B, Fig. 2) immediately over the third row of corn, by which means the implement cannot receive any injury.
For hoeing corn at 12 inches apart, the horse should be conducted along the second space, between the rows or drills, computing the spaces from the left side of the five rows, drilled at one operation of the machine.—The man attending the hoes, ought carefully to keep the pin (B, Fig. 2) directly over the middle of the second space, described as above: this rule will apply to the hoeing of ground at various distances.
Different soils require to be hoed with shares of a proportionate size, which experience alone can ascertain. In light sandy loams, or any other soils sufficiently pulverised, shares from 5 to 6 inches broad, for 9 inch drills, and 8 inches broad for 12 inch drills, may be safely and effectually worked: for strong clays intermixed with pebbles, the hoe-shares should be somewhat less in breadth. But, if the soil, in the spaces of the rows of corn, be pulverized with long narrow plates of iron, similar to chisels, being introduced into the shanks of the hoe-share, A, A, A, A, A, A, (Fig. 2) instead of hoe-plates, the advantages resulting from such a process will be very considerable.
Beside the hoeing of drilled corn, this horse-hoe may be applied to many useful purposes, particularly for cutting up the rows of stubble, as soon as the crop is harvested, together with such weeds as may have escaped the hoe: it may also be employed for the stirring of fallows, &c. after the rate of 10 acres per day, with one man, a boy, and two horses, especially in the busy time of harvest, when it would be impossible to spare so many men and horses as are required to break up the land effectually with the common ploughs.
The price of Mr. Cooke's Improved Drill-plough, together with Horse-hoe, &c. was in the year 1790, twelve guineas.
Excellent, however, as Mr. Cooke's machine unquestionably is, it must be acknowledged, that in some parts it is too complicated. This circumstance has induced Dr. Darwin to apply his versatile talents to the purpose of devising improvements in the construction of this grand national plough, which will transmit his name to posterity, as an enlightened agriculturist, no less than a medical philosopher who has deeply searched into the recesses of Nature.—Of these essential improvements we are (by the liberality of Mr. Johnson, the publisher of Dr. Darwin's classical work, entitled "Phytologia, or the Philosophy of Agriculture,") enabled to communicate accurate engravings, together with an analysis of the subject, contained in the appendix to that useful book.
Description of the Plates representing Dr. Darwin's improvement of the Drill-plough.
Plate I. Fig. 1, a, a, are the shafts for the horse, fixed to the centre of the axle-tree, by a simple universal joint at z, from which, if the horse move in an oblique course, either spontaneously, or designedly, to avoid trampling the rows of corn, in hoeing, the person guiding the plough behind, may keep the coulters in any direction at pleasure:—b, b, are shafts or handles behind, for the man who attends the drill coulters or hoes: these handles are applied to the axle-tree before, and have a transverse piece about 6 inches from the latter at g, g, in order to support the seed-box (Fig. 2.)—At the distance of about one foot behind this, there is another cross piece at c, c, called the coulter-beam, which is about 4 feet 2 inches long, 6 inches wide, and 2 inches thick: it is perforated with 2 sets of square holes, each set consisting of six, to receive the coulters in drill ploughing and the hoes in horse hoeing.
The light square holes are 9 inches distant, and are designed to receive the coulters, or hoes in the cultivation of wheat, the rows of which are to be 9 inches apart: the six dark square holes are 7 inches from each other, for the reception of the coulters or hoes in the cultivation of barley, the rows of which are to be at the distance of only 7 inches. This coulter-beam has likewise 6 circular holes at one end, and 6 round iron staples fixed into the edge of the other part of it: into these are inserted the ends of the tin flues, which intersect each other, and convey the seed from the bottom of the box into the drills or furrows, when the coulters are properly arranged in the square holes. The person guiding the machine can raise these coulters, or hoes, out of the ground, when passing to or from the field, or in turning at the end of the land; and may thus suspend them on the iron springs d, d, which at the same time fix the shafts to the axle-tree, so that the wheels will follow in a similar direction with the horse.—e, e, are wheels, four feet 
Dr. Darwin's Improvements of the Drill-plough
Copied by Permission
in diameter, upon the nave of one of which is a cast-iron at f, f, to turn the axis of the seed-box, which has a similar wheel, but only one-fourth of its diameter, so that the axis of the seed-box revolves four times to one revolution of the wheel.
Fig. 2, is the seed-box, consisting of boards about 1 inch thick, 48 inches in length within, 12 in depth, of a similar width at the top, and 6 inches wide at the bottom. It is divided into six compartments for the reception of grain, and ought to have a cover with hinges, to exclude the rain. This box is to be placed partly over, and partly before the axle-tree of the machine, as delineated at g, g, in Fig. 1. Beneath the seed-box passes a wooden cylinder at h, h, the circumference of which is excavated for the reception of grain from the six cells marked l, m, n, o, p, q; and for conveying it to the six oblique tin flues, i, i, which intersect each other, as represented in Plate I. Fig. 2. By this reciprocal crossing, the seed-flues are designed to increase the length of the inclined surface on which the seed descends, in order that, if six or eight grains be delivered at the same time, they may so separate by their friction, when descending, that they cannot be sown together on the same spot, which might occasion tussocks of corn.
As these seed-flues intersect each other before they pass through the coulter-beam at c, c, (Plate I. Fig. 1), it became necessary to make 3 of the circular holes, at one end of the coulter-beam, more backward than those at the other; and, therefore to use iron staples or rings at one end, instead of perforations, as at w, w, (Fig. 1.) These tin flues deliver the seed into the small furrows, or drills, which are made by the coulters before them. The seed-flues have a joint at z, z, where one part of the tin tubes slides into the other part, by which means the former can be occasionally shortened or lengthened, in order to adapt them to the coulters, when placed 7 inches apart, for sowing barley; or, at the distance of 9 inches, for sowing wheat. In the bottom of this seed-box are 6 holes, one in each compartment, for conveying the corn into the excavations of the cylinder, revolving beneath them. These holes are provided, on the descending side, as the cylinder revolves, with a strong brush of bristles, about 34 of an inch in length, which press hard on the tin cylinder. The holes in the bottom of the seed-box, on the ascending side of the revolving cylinder, are furnished with a piece of strong leather (such as is used for the soles of shoes), which rubs upon that side of the cylinder; by which means the corn, of whatever kind, is exactly delivered, while the axis is revolving, without a single grain being cut, or bruised.
Fig. 3, Is the iron axis, and wooden cylinder beneath the seed-box. An iron bar is first made, about 4 feet 6 inches long, and 1 inch square, the weight of which ought to be about 15lbs.; it is covered with wood, so as to form a cylinder 4 feet in length, and 2 inches in diameter, represented at r, r, in this figure. The use of the iron bar in the centre of the wood, is to prevent it from warping, a circumstance of great importance. This wooden cylinder passes beneath the seed-box, and has a cast-iron cog-wheel at one end of its axis, as at r, r, which is one-fourth of the diameter of the correspondent cast-iron wheel, fixed on the nave ct the carriage-wheel, as in Fig. 1, f, f, so that the axis of the seed-box revolves 4 times during one revolution of the carriage wheels.
In the circumference of this wooden cylinder are excavated four lines of holes, consisting of six in each line, as at n, n, n, n, n, n. A similar line of excavations is made opposite to these, on the other side of the cylinder, and between these are two other rows of holes, amounting in the whole to twenty-four excavations in the wooden part of the axis beneath the seed-box, for the purpose of receiving and conveying the corn from the seed-cells into the flues o, o, i, i, (Fig. 2), while the axis is revolving: in which respect this improvement of Dr. Darwin bears some analogy to the original design of the celebrated Mr. Tull.
These excavations are one inch in length, half an inch in width, and three-eighths of an inch in depth, which dimensions are too large for any seeds employed at present in large quantities, except beans; but which may be contracted to any dimensions required, by moving the cylinder over the wooden one, as will be immediately explained.
Fig. 4, A, B, represents a tin cylinder one inch longer within, than the wooden cylinder on the iron axis at Fig. 3: it is 2 inches in diameter within, so as exactly to fit the wooden cylinder, which may slide within it about an inch backwards or forwards.—C, D, are two square sockets of tin, fixed on the ends of the tin cylinder to fit on the square part of the iron axis, passing through the wooden cylinder at l, l, Fig. 3, on which they slide one inch, as before.
The following directions for perforating the holes, both in the tin and wooden cylinders, which are mutually to correspond, Dr. Darwin recommends to be strictly attended to.
1. When the tin cylinder is soldered longitudinally, and one end of it is thus fixed, as at A, six holes ought to be made through it lengthwise on its four opposite sides; each hole must be exactly one half of an inch in width, and 5-8ths of an inch in length, which should be parallel to that of the cylinder. The centre of the first of these holes ought to be five inches distant from the closed end A; and that of the second hole, eight inches apart from the centre of the first; and the others in the same proportion, till six holes are made longitudinally along the cylinder. Another line of six similar holes is then to be made on the opposite side of the cylinder; and after that, two other such lines between the former; the number of holes amounting in the whole to 24, the dimensions of all which should be exactly observed, as well as their distances.
2. The wooden cylinder, fixed on the axis, is now to be introduced into that of tin, so as to leave the exact space of one inch void, at the closed end A; when the size of all these apertures through the tin cylinder (each of which is exactly half an inch in width, and 5-eighths of an inch in length), should be carefully marked with a fine point on the wooden cylinder, which ought not to be previously excavated.
3. The 24 holes, thus marked on the wooden cylinder, are now to be excavated precisely 3-eighths of an inch in depth, to which are to be added 3-eighths of an inch at that end of each of them which is nearest to A; so that, when the wooden cylinder is again replaced in the tin cylinder as before, with one inch of void space at its closed extremity, the excavations in the former will be 3-eighths of an inch longer than the perforations over them in the latter. These excavations in the wooden cylinder should, likewise, be somewhat narrower at the bottom, effectually to prevent any of the grain from sticking in them, while revolving.
4. An iron screw, about three inches in length, with a square head for the reception of a screw-driver, should be passed through the end A, of the tin cylinder on one side of the axis, as at C, in Fig. 4. The screwing part of this must lie in a hollow groove of the wooden cylinder, and be received into a nut, or female screw, fixed to the same cylinder. The head of the screw, passing through the end A, of the tin cylinder at C, should have a shoulder within the tin cylinder, to prevent it from penetrating through the end of it. A brass ring should also be put over the square end of the screw, on the outside of the tin cylinder, through which end a pin ought to pass, in order to keep the ring steady. Thus, when the square head is turned by a screw-driver, it gradually moves the tin cylinder one inch backwards and forwards on that of wood; so as either to press the end A of the tin cylinder into contact with that of the wooden cylinder within it, or to remove it to the distance of one inch, and leave a void space at the end A.
5. The ends of all the holes of the tin cylinder are next to be enlarged, by slitting the tin 3-eighths of an inch towards A, on each side of the hole; that part, however, of the tin included between these two slits (which will be half an inch wide, and 3-eighths of an inch in length, with respect to the cylinder), is not to be cut out, but bent down into the excavations of the wooden cylinder beneath, so as to lie against that end which is nearest to it.—But, before these pieces of tin are bent down, as just described, they should be filed somewhat smaller at the projecting than at the other end; because the excavations of the wooden cylinder are to be rather narrower at the bottom than at the top; and these pieces of tin, when bent down, ought to fit them exactly.
Lastly, When all these holes are thus enlarged, and the bits of tin filed somewhat narrow at their projecting ends, and then bent down into the excavations of the wooden cylinder, the other end of the tin cylinder, with its square socket, may be soldered on. Thus, when the end of the tin cylinder at A, is pressed forwards upon the wooden one towards B, by turning the screw at C, above described, all the excavations of the wooden cylinder will be gradually lessened, and at length entirely closed; by which means they may be adapted for the reception and delivering of seeds of any size, from horse-beans and peas to wheat, barley, and turnip-seed, with the utmost accuracy, so as to sow 4, 5, or 6 pecks per acre, or more or less, at the pleasure of the cultivator, merely by turning the screw a few revolutions, in either direction.
In farther illustration of these principles, or directions, Dr. Darwin observes:
1. That in constructing tin and wooden cylinders beneath the seed-box, another small improvement may become necessary in sowing very small seeds, namely, when the screw at the end A, is turned, so as to contract all the excavations of the wooden cylinder, its surface will become bare for the space of one inch from the end of each excavation towards the end B, (Plate I. Fig. 4), without being covered by the tin cylinder. On these exposed parts, which will be one inch long, and half an inch wide, some seeds may accidentally stick, and evade the brushes which are to prevent them from passing, while the cylinders revolve. To remedy this inconvenience, when the wooden cylinder is placed within the tin one, in such a direction that all the holes are completely open, Dr. Darwin recommends a piece of the tin cylinder, about an inch and an half in length, and half an inch in width, to be cut out from the extremity of each hole next to the end B, and such piece to be fixed by a few sprigs on the wooden cylinder, exactly in the same place it covered previously to its being cut out of the tin one; by which means, when the tin cylinder is afterwards pushed forwards, by turning the screw at its end, so as to contract the excavations of the wooden cylinder beneath, its bare parts will be an inch and a half distant from the extremities of the excavations next to the end B; and thus will not pass under the brushes: consequently no small seeds can be lodged in them.
2. Some kind of iron staple ought to be fixed on the outside, at each end of the seed-box, to catch hold of the two springs at d, d, (Plate I. Fig. 1), when the hinder part of the carriage is elevated by the man guiding it, in order to suspend the coulters out of the ground, and to connect the hinder part of the machine with the shafts before: so that, when turning at the ends of the lands, or passing to or from the field, the wheels may not deviate from the joint z, at the centre of the axie-tree, but may follow in the same lines as the shafts.
3. The seed-box should likewise be supported on erect iron pins, passing through staples of that material; with a lever under the end of it, next to the wheel r, r, (Plate I. Fig. 3), in order to lift easily that end of the seed-box, about an inch high, and to raise the teeth of the iron cog-wheel on its axis out of the teeth of the correspondent iron one, on the nave of the carriage-wheel.
4. The construction of the coulters winch make the drills, and of the rakes, by which they are filled after the seed is deposited, and also of the hoes, are not delineated; as they resemble those employed by persons practising the drill husbandry, and which we have already described, when treating of Mr. Cooke's patent machine.
5. When the lower ends of the seed-flues are placed through the holes in the coulter-beam (Plate I. Fig. 1), at the distance of 9 inches from each other, the rows of wheat or beans will be 9 inches apart: hence, as the wheels of the carriage are 4 feet in diameter, and therefore move about 12 feet at every revolution; and, as there are 4 excavations round the axis of the seed-box, which revolve 4 times to one revolution of the carriage-wheels, consequently the seeds contained in the excavations of the cylinder beneath the seed-box, will be sown at 9 inches distance in each drill or furrow, while the plough is proceeding.
6. By Mr. Cooke's drill-plough, the quantity of seed sown on an acre is 6 or 7 pecks, that is, about half the quantity used in broad-cast sowing. If the wheat be exactly deposited in the drill, Dr. Darwin is of opinion that one bushel will be fully sufficient for an acre, as the rows are 9 inches apart from each other: for then 8 or 9 grains would be dispersed in every 9 inches of the drill furrow; namely, in every square of 9 inches surface of the land so cultivated.—This may be more clearly ascertained by the following data: Mr. Charles Miller, in the "Philosophical Transactions," vol. lviii. has calculated the number of grains in a bushel of wheat to amount to 620,000; Mr. Swanwick, of Derby, has lately computed them at 645,000; Dr. Darwin, therefore, concludes that a bushel, on an average, contains 635,000 grains of wheat. A statute acre comprises 4,840 square yards, each of which contains 16 squares of 9 inches: if 4,840 be multiplied by 16, the produce will be 77,440, which is the number of squares of 9 inches in such an acre. If 635,000 grains in a bushel be divided by 77,440, (the number of squares of inches in an acre), the quotient will shew, that somewhat more than 8 grains of wheat will thus be deposited in every 9 inches of the drills.
7. If 8 or 9 grains be dropped at the same time in one inch of ground, they will, if they all should grow together, be too numerous, and form a tussock; but, by making them slide down an inclined plane, from the seed-box to the coulters, as in the tin flues, which are crossed in order to lengthen them (Plate I. Fig. 2), some of the seeds will, by their friction while descending, be retarded more than others; and the 8 or 9 seeds will thus be scattered over the whole 9 inches of the drill; which renders this method of sowing far superior to that of dibbling; because, in the latter, all the seeds are dropped together.
8. When the holes in the wooden cylinder are entirely open, they are of a proper size for the sowing of horse-beans, or peas: when they are perfectly closed, there will remain a small niche at the end of the excavation in the wooden cylinder, nearest to B (Plate I. Fig. 4), for turnip, or other small seeds. For wheat, barley, and oats, a wooden wedge ought to be made exactly of the same shape as the area of the hole, which the director of the plough requires, who will insert it occasionally in the holes, when he turns the screw at the end of the cylinder, in order to enlarge, or reduce them, according to those dimensions. On these wedges ought to be written, with white paint, wheat, barley, oats, &c. which will considerably facilitate the accommodating of the size of the excavations to each kind of grain; and which may be altered, if requisite, to suit larger or smaller seeds of the same species.
9. In some drill-ploughs, for instance in Mr. Cooke's, there is some additional machinery for drawing a line, while the plough proceeds, in which the wheel that is next to the last-sown furrow, may be directed to pass at a proper distance from, and parallel to it. This, however, may be effected, when sowing wheat, or peas and beans, by making the wheels, while they run on the ground, at the exact distance of 54 inches from each other; and, at the time of sowing, by guiding the wheel nearest to the part last sown exactly in the rut last formed; by which means every row will be accurately made, at the distance of 9 inches.
To these observations, Dr. Darwin has subjoined some remarks, tending to evince, by comparison, the essential improvements he has made on this complicated machinery, and from which we extract the following:
1. The simplicity of his drill-plough consists, first, in its having a seed-box only, and not a seed-box and hopper, as is the case with Mr. Cooke's patent drill-plough.
2. The flues, conducting the seed from the bottom of the box into the drill furrows, are not disjoined in the middle, to permit the lower part to move either to the right or left, when the horse deviates from the line in which the coulters pass, as in Mr. Cooke's plough: this defect may be remedied by the simple universal joint at z, (Plate I. Fig. 1).
3. In this machine, the shafts behind, between which the man guiding the coulters walks, are fixed to the coulter-beam, as well as to the axle-tree; whereas, in Mr. Cooke's patent drill-plough, all these are moveable joints, similar to a parallel rule, in order to counteract the swerving of the horse: which, in this machine, is effected by the simple universal joint at z, (Plate I. Fig. 1), already described.
4. The dimensions of the holes in the axis of the seed-box, are here likewise altered, merely by turning a screw, so as to accommodate them to every kind of seeds, which are usually sown on fields, or arable lands.
5. The strong brush of bristles, which sweep over the excavations of the cylinders beneath the seed-box, and strickle them so exactly, that no supernumerary seeds escape; and yet none are either bruised or broken, which sometimes happens in Mr. Tull's original machine.
Lastly, Dr. Darwin justly observes, that the cheaper and more simple the machine is in its construction, the less liable will it be to accidents, which occasion expences in its repair; and, with the greater facility will its management be understood; all which circumstances correspond with its greater simplicity: and, we cordially hope with the Doctor, that the practice of the drill-husbandry will thus be more generally diffused.
Plate II. Fig. 1, is a seed-box, invented by Mr. Swanwick, of Derby, who has liberally offered to shew the working models of the seed-boxes, or to assist any person who may wish to construct either this drill machine, or the preceding one, invented by Dr. Darwin.
Mr. Swanwick's seed-box is 48 inches in length within, and is divided into 6 cells, for the purpose of sowing 6 rows of seeds at the same time, similar to that above specified. At the bottom of each cell is a hole a, a, a, a, a, a, (Fig. 1), through which the seed passes into the seed-flues, as in the machine before described; but this has no revolving axis, there being 
Dr. Darwin's Improvements of the Drill-plough.
(Copied by Permission.)
only a wooden or iron bar, B, B, (Fig 3), about 2 inches broad, 4 feet 8 inches long, and exactly 3-eighths of an inch thick. Through this bar 6 holes are perforated, marked e, e, e, &c. each of which is exactly one inch in length, half an inch in width, and 3-eighths of an inch in depth, which is the same as the thickness of the bar. The centres of these holes are exactly 8 inches distant from each other, corresponding to the holes at the bottom of the seed-box, over which it is made to slide backwards and forwards in a groove. By this sliding motion, it passes under stiff brushes which are placed over it on each end of the holes, at the bottom of the seed-box, and strickle off the grain, as the holes in the sliding-bar pass under them, which thus distribute the quantity with considerable accuracy.
In order to increase, or diminish, the proportion of grain to be delivered, the slider is covered with a tin-case, C, C, (Fig. 4,) which is perforated with six holes, corresponding with those in the slider: instead, however, of the bit of tin being cut out the full length of the hole, part of it is left at the end equal to the thickness of the slider, and is bent down, after the slider is put into the case, in the same manner as the tin cylinder in the preceding machine. This case is moveable about one inch, backward and forward, by turning the finger-screw s (Fig. 4 and 5), by which the holes are enlarged, or diminished, for the purpose of adapting them to various sorts of grain, or different quantities of the same sort, exactly as in the tin and wooden cylinders in Plate I.—The slider is moved forwards by a bent iron pin, h, attached to it, which passes into a serpentine groove, Y, (Fig. 5), fixed to the nave of the wheel: it is likewise moved backwards by a steel spring at the other end of the seed-box, but which is not delineated in the Plate.
Fig. 5, is a bird's-eye view of the parts before described:—E, E, the seed-box divided into cells or compartments, by the partitions d, d, d.—c, c, c, the slider, with part of the apertures seen just appearing from under the brushes.—X is the axis of the wheel.
Fig. 2, represents a side view of one of the six bridges lying over the holes at the bottom of the seed-box, on each side of which the brushes are fixed, which strickle the holes when full of corn, while the bar slides backwards and forwards. The simplicity of this slider at the bottom of the seed-box, Dr. D. observes, may be, in some instances, greater than that of wooden and tin cylinders in his machine, as Mr. Swanwick's has only six holes for distributing the quantity of corn, whereas the former has twenty-four. In other respects, it is, perhaps, more complicated; as twelves brushes are used, one on each side of the six holes, whereas there are only six brushes rubbing on the tin cylinder in the former machine. The reciprocating motion of this slider must be quick, as it necessarily acts once every time the circumference of the carriage-wheel passes nine inches forward, which may not be so easy to execute as the cog-wheel, with the uninterrupted movement of the axis and cylinder in the preceding machine.
Lastly, Dr. Darwin concludes with remarking, that the facility of adapting the holes to the dimensions required in both machines, and the circumstance, that they neither bruise nor break the grain, and are not encumbered with an additional hopper, which must deliver the quantity of seed with great inaccuracy, from the unequal shaking of the machine, considerably add to the excellence and simplicity of both.
Another implement upon a new principle was invented by Mr. John Horn, of Dover, and by him denominated an "Universal sowing machine, for drilling or broad-casting;" for which he obtained a patent, about the year 1785. It is so constructed that, whether worked by the hand, drawn by a horse, or fixed to and used with a plough, it is not liable to be put out of order; there being but one movement to direct the whole. It sows every kind of grain with equal ease and regularity, so that the quantity sown may be varied at pleasure, and in any degree. A correspondent in the 12th vol. of "Annals of Agriculture," p. 481, states, that Mr. Horn's invention possesses the peculiar advantage of cultivating turnips, so as to ensure the crop against the ravages of the fly. By sowing the usual quantity of turnip-seed broad-cast by the machine, and at the same time striking furrows at proper distances in the land, part is deposited in the drills, and the rest sown broad-cast between them: so that, if the season be dry, it will be favourable to the drills, and, if wet, to that which is broad-cast. And, if it happen that the latter be injured by the depredations of the fly, the former, by coming at a later period, is saved; or, if the former be destroyed, the latter is preserved. If the whole thrive, the farmer has the choice of selecting the most vigorous plants from both.—The price of this valuable implement, if constructed so as to be used with a single-furrow plough, is, we understand, 312 guineas:—if intended for a double-furrow plough, 412 guineas:—that of the large machine, consisting of a seven-furrow plough, with Mr. Horn's additions, the whole made by himself, is 712 guineas.—For a more particular account, we refer the reader to a treatise on the subject, published by the inventor (8vo. 6d. Johnson, 1786), entitled "Description and Use of the Universal Sowing Machine for Drilling and Broad-casting."
In the 12th vol. of Annals of Agriculture, p. 197, we also meet with a communication from a Mr. J. Harvey, of Elmley, in which he announces his invention of an engine that plants every kind of grain in a manner, he conceives, never before attempted. It is a common wheel-plough, to which is fixed a simple piece of machinery, for conveying, by means of an engine fixed to the plough, immediately behind the mould-board, any quantity of grain into an incision in the heart of a furrow, of whatever depth: the seed is effectually and instantly covered by an instrument suspended to the engine. The whole machinery consists of iron, yet does not exceed 20lb. in weight.—The engine may be worked without a handle (unless at the end), which does not retard the sowing, or add much to the labour of the horses. The inventor observes, that it may be employed on any soil, and in all seasons; the seed being covered to protect it from the effects of the weather.—The price of Mr. Harvey's implement, exclusively of the plough to which it is fixed, does not exceed three guineas.
The last of these various contrivances, of which we shall take notice, is the Drill and Hoe-Plough, invented a few years since by a Mr. Ridge, of which an engraving is given in the 60th vol. of the Gent. Magazine, for 1790; where its principles and mechanism are described.—This machine is so constructed that, by means of a handle, the man employed has power to hold or guide it in a strait direction, without any attention to the going of the horse being requisite, farther than is rendered necessary in a common plough: and, whether the implement be drawn up, or down a hill, or horizontally, it deposits the corn with equal regularity, and at any given depth; so that none of the seed will be buried too deeply in the earth, or exposed to perish on the surface. Thus, it is asserted, one-third of the usual quantity of seed may, in general, be saved; and, in some cases, more than one-half.
The wheels on which Mr. Ridge's plough moves, are half a rod in circumference; and, by computing their revolutions, when they have once passed over the field, the portion of seed sown may be ascertained, if the machine be supplied with a certain quantity. The number of acres that can thus be drilled in one day, depends on the distance at which the rows of corn are set. Stones, it is said, are no obstruction to the drilling of corn, by means of this implement; provided they be not too large to pass between the fines, or tubes, which deliver the seed to the ground.
The plough here alluded to, may be used for sowing every kind of grain, or seeds, not only with facility and regularity, but also without bruising them; and, as soon as the crop grows up, it may be employed with equal advantage as a horse-hoe. Its construction is stated to be so simple, that in half an hour a common ploughman may be made to comprehend its movements, sufficiently to be entrusted with it for the whole season. On level soils, one horse, in general, will be fully competent to draw it; but, in ascending steep hills, or on very stiff land, two will become necessary.—The price of this expensive implement, we understand, is about 14 guineas.
For a more particular account of the drilling system, we must refer our readers to Mr. Amos's "Theory and Practice of Drill-Husbandry," (4to. 18s.) published a few years since, in which the matter is fully investigated, and the advantages and disadvantages are fairly appreciated. But those, who wish to acquire only a general knowledge of this important practice, we advise to peruse the Rev. Mr. Cooke's pamphlet (12mo. price 6d.) entitled, "Drill-Husbandry perfected."
Before we conclude this highly important subject, it will be useful to state the extraordinary national saving that would arise from a general introduction of the drill-husbandry. Indeed, the patriotic Lord Somerville, late President of the Board of Agriculture, whose exertions in promoting that beneficial science, must endear him to every friend of his country, has already anticipated our calculations. Though bred to the broad-cast method, which he till lately followed, that enlightened Nobleman has, in the Appendix to his interesting work, entitled "The System followed during the two last years by the Board of Agriculture," &c. (8vo. pp. 300, Miller, 1800), impartially exhibited the great advantages that might result from the national adoption of the drill-husbandry. We regret that our limits will permit us only to extract a few leading circumstances from his Lordship's publication. In order to ascertain, beyond the possibility of doubt, the infinite superiority of the drilling, over that of the broad-cast method of sowing, he applied to three gentlemen alike eminent for their agricultural skill, and each of whom made use of different drill-ploughs. From an accurate statement it appears, that the expences attendant on the old and new practices, are as follow:
| Expence of seed-corn on 133 acres of land, sown in the usual broad-cast husbandry in 1799, was--£. | 134 | 10 | 6 |
| The expence of seed-corn for the same number of acres, according to the present improved system of drilling, | 100 | 4 | 6 |
| In the year 1800, the expence of 140 acres broad-cast, was Ditto,---ditto,-drilled,- | 92 | 0 | 0 |
| Which affords a saving of not less than----in seed-corn on 140 acres of land. | 124 | 10 | 0 |
Both estimates were made from actual experience, by the industrious Mr. Budden, and communicated to Lord Somerville by the Rev. H. J. Close, of Hordle, near Lymington; from whose letter we insert the following computation of an annual saving that may be effected by the uniform practice of the drill-husbandry; and which, at a moderate calculation, will amount to not less than eight millions of bushels of wheat, one million of bushels of rye, three millions of bushels of barley, four millions of bushels of oats, and one million of bushels of beans and peas!
Having, however, in the course of attentive observation, during the last twenty years, witnessed many disappointments, both in statistical and political schemes, we are not so sanguine in our expectations, as to place implicit confidence on any general statement, especially when it is exemplified by round numbers. Nevertheless, in justice to the zealous supporters of the drill-plough, we fully admit its superiority over the clumsy and irregular practice of the wasteful broad-cast husbandry; and posterity will ever gratefully remember the names of Tull, Cooke, Young, and Darwin, if, by their joint labours, one half of the above stated quantity of grain and seeds, that is, together eight or nine millions of bushels, could be annually saved to the nation, before one half of the present eventful century is expired.