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into neglect. The oldest book in which it is friable; giving greater facility to the protection mentioned is probably The Country Gentleman's of redundant moisture, and to the spreading or Companion, by Stephen Switzer, gardener, Lon- the roots of vegetables in quest of food. The don, 1732. In that work it is stated that the application of as much water, sand, or any simiearl of Halifax was the inventor of this useful lar substance, would have exactly the same effect improvement; and that it was much practised in opening, and keeping open, the pores of an in Sussex. There are engravings of two kilns adhesive clay soil, and converting it into the for burning clay, one adopted in England, and quality loam. Besides this, which would be a the other in Scotland; where it is said to have permanent improvement upon the staple or texbeen ascertained that lands, reduced by tillage to ture of every clay soil, burnt clay or torrefied poverty, would produce an excellent crop of tur- earth may sometimes acquire, in this operation, nips if the ground were ploughed two or three a small quantity of soot or carbonic matter, that times, and clay ashes spread over it. In the may, in favorable circumstances, operate for one same work there are several letters, written in season as a manure, or as a stimulus to a small the years 1730 and 1731, stating that the plan extent to the growth of vegetables. This at of burning clay had answered in several parts of least may be the case if the clay or earth burnt England; and accounts were received from Scot- shall abound with vegetable matter, and if the land that, upon experiment, it bad answered burning is conducted in such a smothered way better than either lime or dung, but was found as to prevent the smoke or vegetable inatter from too expensive. The practice is described at escaping. But as it is the subsoil that is recomlength in Ellis's Practical Farmer, or Hertford- mended, and seems to be generally used for shire Husbandman, 1732. In 1786 James Ar- burning, it is impossible any considerable quanbuthnot, of Peterhead, tried several successful tity of vegetable matter can be found in it. The experiments with burning clay, and various calcareous matter in the soil, it is said, will be others have since been made in different parts calcined and formed into lime by the operation of the empire. In 1814 the practice was revived of burning. But I am disposed to consider this and written ou by Craig, of Callay, near Dum- argument as far more plausible than solid. Calfries, and soon after by general Beatson, near careous matter is no doubt found, on chemical Tunbridge ; by Curwen, Burrows, and several analysis, to a certain extent in some soils ; percorrespondents of agricultural journals. In haps some perceptible portion of it may be found Ireland, it would appear, the practice prevails in in every soil. But it is seldom or never found several places, and Craig says he adopted it from in any soil to such an extent as to be of much seeing its effects there. The result of the whole use as a manure to other land. Even when the is, that the benefits of this mode of manuring soil is impregnated with a large portion of calcahave been greatly exaggerated ; though they reous matter, if it is not in the form of limestone, certainly appear to be considerable on clayey but minutely mixed with it, the burning cannot soils. Aiton (Farmer's Magazine, vol. xxii. p. either increase or much alter the lime. If it is 423) compares this rage for burning clay, which in the form of stones, however stoall, or in what existed in 1815, to the fiorin mania of a few years is called limestone gravel, there is little chance prior date. In 1822 he found few of the advo- of its being calcined in the operation of burning cates for these improvements disposed to say the clay ; it would go through that ordeal unalmuch on the subject, and saw very few clay tered. Any change, therefore, that can be kilns smoking. To give my ultimatum upon made upon the small portion of calcareous this subject,' he says, I regret that the disco- matter in the soil, by burning in the manner diverers of fiorin grass, and of the effects of burnt rected, can scarcely have any perceptible effect clay, have so far overrated their value. Both are when that matter is applied as manure to other useful and proper to be attended to ;-the grass soils. And though it is possible that some quato be raised on patches of marshy ground, and lities in particular soils, unfavorable to vegetaused as green food to cattle in winter; and the tion, may be corrected by burning, and that in burnt earth as a corrector of the mechanical ar- some other instances the fire may render the clay rangement of a stubborn clay soil; and I have more nutritive to plants (though I have not been no doubt but if they had been only recommended able to trace this, or even to conjecture how it for those valuable purposes they would have been can happen), yet I am much disposed to believe brought into more general use than they yet are that its effect as a mechanical mixture in opening or will be, till the prejudice against them, arising the pores of the soil is the chief improvement from the disappointment of expectations raised that can be derived from the application of burnt high by too flattering descriptions, are removed.' clay as a manure. If it has any other effect it He thus describes the action of burnt clay :- must be from the soot or carbonic matter collected • It must be obvious to every person that bas during the operation of burning; or perhaps it paid attention to the subject, that when clay, or may acquire by the torrefaction somewhat of a other earth, is burnt into ashes like brick-dust, stimulating quality, that may for a short time it will not (unless acids be applied to it) return promote the growth of particular plants. But again to its former state of clay, but will remain these qualities can only be to a small extent, in the granulated state of ashes or friable mould, and continue to act for a very limited period.'to which it was reduced by the operation of Far. Mag. xxii. 422. burning. An admixture of this kind, with a According to a writer in the Farmer's Journal strong adhesive clay, must evidently operate as the action of burnt clay is at least three-fold, a powerful manure by changing the mechanical and may be manifold. It opens the texture o. arrangement of the latter and rendering it more stubborn clays, gives a drain to the water, spira

cles to the air, and affords to the roots facility of air-pipes are of use only at first, because, if the penetrating. Clay ashes burned from turves, fire burns with tolerable keenness, the sods formcontaining an admixture of vegetable matter, ing the pipes will soon be reduced to ashes. The consist, in some small proportion, of vegetable pipe on the weather side of the kiln oply is left alkali, or potassa, a salt which is known to be a open, the mouths of the other three being stopped good manure. It also, in most cases, happens, up, and not opened, except the wind should veer that a stiff cold clay is impregnated with pyrites, about. As the inside of the enclosure, or kila, a compound of sulphuric acid and iron. Als begins to be filled up with clay, the outer wall though the chemical attraction between these two must be raised in height, always taking care to bodies is so strong that it is one of the most dif have it at least fifteen inches higher than the top ficult operations in the arts totally to free iron of the clay, for the purpose of keeping the wind from sulphur, yet a very moderate heat sublimes from acting on the fire. When the fire burns a large portion of the sulphur. The iron is then through the outer wall, which it often does, and left at liberty to re-absorb a portion of the redun- particularly when the top is overloaded with dant sulphuric acid, which toc generally is found clay, the broach must be stopped up immedi. in these soils, and thereby sweetens the land; ately, which can only be effectually done by. and it is probable that the bright red, or crimson building another sod wall from the foundation, calx of iron, which gives coloring to the ashes opposite to it, and the sods that formed that part when over burnt, is beneficial to vegetation in of the first wall are soon reduced to ashes. The the present case, inasmuch as it is, of itself, one wall can be raised as high as may be convenient of the happiest aids to fertility, as is exemplified to throw on the clay, and the kiln may be inin the red marl strata, and red sand strata creased to any size, by forming a new wall when throughout the kingdom. The evolution and re- the previous one is burnt through. The princicombination of different gases, no doubt, mate- pal art consists in having the outer wall made rially affect the question ; but it is reserved for quite close and impervious to the external air, accurate chemical observers to give us an account and taking care to have the top always lightly, of the processes which take place in this respect. but completely covered with clay ; because, if Curwen notices that clay ashes do no benefit as the external air should come in contact with the a top dressing on grass, which is in part to be fire, either on the top of the kiln, or by means of explained by reason that the ashes, when spread its bursting through the sides, the fire will be on the surface of the grass, cannot exert the me- very soon extinguished. In short, the kiln rechanical action on the soil in the ways enume- quires to be attended to nearly as closely as charrated. Neither can the calx of iron come so im- coal pits. Clay is much easier burnt than either mediately in contact with the particles of the soil, moss or loam ;-it does not undergo any alterafor the producing of any chemical effect, as it tion in its shape, and on that account allows the would do if the ashes were ploughed in. In fire and smoke to get up easily between the short, like many other manures which are laid on lumps; whereas moss and loam,' by crumbling the surface, unless it contains something soluble down, are very apt to smother the fire, unless carewhich may be washed into the ground by rains, fully attended to. No rule can be laid down for it does very little good ; and the feeble propor- regulating the sixe of the lumps of clay thrown tion of vegetable alkali is probably the only so- on the kiln, as that must depend on the state of luble matter the ashes contain. However san. the fire; but I have found every lump completely guine may be the admirers of burnt clay, all burnt on opening the kiln; and some of them experience confirms that the most beneficial clay- were thrown on larger than my head. Clay, no ashes are those which are burnt from the greatest doubt, burns more readily if it be dug up and proportion of rich old turf, ancient banks, roots dried for a day or two before it be thrown on of bushes, and other vegetable matters; and I the kiln; but this operation is not necessary, as conceive the value of mere powdered pottery it will burn though thrown on quite wet. After (for such it is) may easily be overrated. —Far. a kiln is fairly set a going, no coal or wood, or Journ. 1819.

any sort of combustible is necessary, the wet The common method of burning clay is thus clay burning of itself, and it can only be extipdescribed by Mr. Loudon. An oblong enclosure, gnished by intention, or the carelessness of the of the dimensions of a small house (say fifteen operator,-the vicissitudes of the weather having feet by ten), is made of green turf sods, raised hardly any effect on the fire, if properly attended to the height of three and a half or four feet. In to. Ito may, perhaps, be necessary to mention the inside of this enclosure, air-pipes are drawn that, when the kiln is burning with great keendiagonally, which communicate with holes left ness, a stranger to the operation may be apt to at each corner of the exterior wall. These pipes think that the fire is extinguished. If, therefore, are formed of sods put on edge, and the space any person, either through impatience, or too between these so wide only as another sod can great curiosity, should insist on looking into the easily cover. In each of the four spaces left be- interior of the kila, he will certainly retard, and tween the air-pipes and the outer wall, a fire is may possibly extinguish the fire ; for, as before kindled with wood and dry turf, and then the mentioned, the chief art consists in keeping out whole of the inside of the enclosure or kiln filled the external air from the fire. Where there is with dry turf, which is very soon on fire; and abundance of clay, and no great quantity of on the top of that, when well kindled, is thrown green turf, it would perhaps be best to burn the the clay, in small quantities at a tiine, and re- clay in draw-kilns the same as lime. reated as often as necessary, which must be re- Colonel Dickson, at Hexham, and other gentlegulated by the intensity of the burning. The men of Northumberland, instead of building a kiln use gratings or arches of cast iron, to form be laid as dry as possible by proper ridges. A a vault or funnel for the fuel, and over this fun- loamy soil is the medium between these two. It nel the clay is built. The grated arches are ought to be tilled flat in a dry country, especially made about two feet and a half long, two feet if it incline to the soil first mentioned. In a diameter, and about fourteen inches high. One moist country, it ought to be formed into ridges, grating is to be filled with brushwood, stubble, or high or low according to the degree of moisture any other cheap fuel, and the clay, as it is dug, and tendency to clay. built upon it to a convenient height, leaving In grounds that require ridging, an error presmall vacancies, or boring holes, to allow the vails, that ridges cannot be raised too high. But heat to penetrate to the middle and outer parts high ridges labor under several disadvantages. of the clay. When a sufficient quantity is built The soil is heaped upon the crown, leaving the upon the first grating, another is added at either furrows bare ; the crown is too dry, and the furor both ends, filled with similar fuel, and the rows too wet; the crop, which is always best on clay built upon them as before. This process the crown, is more readily shaken with the wind, is continued until ten, twelve, or a greater than where the whole crop is of an equal height; number of the gratings have been used, when the half of the ridge is always covered from the one end is built up or covered with clay, and sun, a disadvantage which is far from being at the other, under the last grating, a fire is slight in a cold climate. High ridges labor unmade of coals or faggot wood. The end at der another disadvantage; in ground that has no which the fire is made should face the wind if more level than barely sufficient to carry off possible, and if the process has been pro- water, they sink the furrows below the level of perly conducted the clay will be effectually the ground; and consequently retain water at burnt. By commencing with a centre grating, the end of every ridge. The furrows ought

in the form of a cross, the workman may build never to be sunk below the level of the ground. • from four ends in the place of two; this con- Water will more effectually be carried off by

trivance will afford a facility in the work, and lessening the ridges both in height and breadth; have a draft of wind at two entrances. The ad- a narrow ridge the crown of which is but eighvantage of this mode of burning clay is the saving teen inches higher than the furrow, has a greater of cartage, as the clay may be always burned slope than a very broad ridge where the differwhere it is dug.

ence is three or four feet. Mr. Curwen has practised burning clay and In forming ridges, where the ground hangs surface soil by lime without fuel (Farm. Mag. vol. considerably, they may be too steep as well as xvi. p. 11, 12), in the following manner :-Mounds too horizontal; and, if to the ridges be given all of seven yards in length, thre? and a half in the steepness of a field, a heavy shower may do breadth, are kindled with seventy-two Winches- irreparable mischief. To prevent this the ridges ter bushels of lime. First, a layer of dry sods ought to be so directed cross the field as to have or parings, on which a quantity of lime is spread, a gentle slope, for carrying off water slowly, and mixing sods with it; then a covering of eight no more. In that respect, a hanging field has inches of sods, on which the other half of the greatly the advantage of one that is nearly horilime is spread, and covered a foot thick : the zontal; because, in the latter, there is no opporheight of the mound being about a yard. In tunity of a choice in forming the ridges. A hill twenty-four hours it will take fire. The lime is of all ground the best adapted for directing the should be immediately from the kiln. It is ridges properly. If the soil be gravelly, it may better to suffer it to ignite itself, than to effect it be ploughed round and round, beginning at the by operation of water. When the fire is fairly bottoin and ascending gradually to the top in a kindled, fresh sods must be applied. Mr. Cur- spiral line. This method of ploughing a hill, wen recommends obtaining a sufficient body of requires no more force than ploughing on a level; ashes before any clay was put on the mounds. and removes the great inconvenience of a gravelly The fire naturally rises to the top. It takes less hill, that rains go off too quickly; for the rain is time, and does more work to draw down the retained in every furrow. If the soil be such as ashes from the top, and not to suffer it to rise to require ridges, they may be directed to any above six feet. The former practice of burning slope that is proper. in kilns was more expensive; did much less To form a field into ridges, that has not been work; and, in many instances, calcined the formerly cultivated, the rules mentioned are ashes, and rendered them of po value.

easily put in execution. After seeing the ad2. Of ridges. The first thing is to consider vantage of forming a field into ridges, people what grounds ought to be formed into ridges, and were naturally led into an error, that the higher what ought to be tilled with a flat surface. Dry the better. But the practice of making their soils, which suffer by want of moisture, ought to ridges crooked certainly did not originate froin be tilled flat, to retain moisture. The method design, but from the laziness of the driver sufferfor such tilling is to go round from the circum- ing the cattle to turn, instead of making them ference to the centre, or from the centre to the finish the ridge without turning. There is more circumference. This method is advantageous than one disadvantage in this slovenly practice. in point of expedition, as the whole is finished First, the water is kept in by the curve at the without once turning the plough. At the same end of every ridge, and sours the ground. Setime, every inch of the soil is moved, instead of condly, as a plough has the least friction possileaving either the crown or the furrow unmoved, ble in a straight line, the friction must be as is commonly done in tilling ridges. Clay soil, increased in a curve, the back part of the mouldwhich suffers by water standing on it, ought to board pressing hard on the one hand, and the coulter pressing hard on the other. Thirdly, On these accounts, if the farmer has not a the plough moving in a straight line has the long lease, it will be in general much his integreatest command in laying the earth over. But, rest to leave the ridges as he found them, rather where the straight line of the plough is applied than to attempt to alter their direction ; and, if to the curvature of a ridge to heighten it by he attends with due caution to moderate the gathering, the earth moved by the plough is con- height of these ridges, he may reap very good tinually falling back, in spite of the most skilful crops. But, where a man is secure of possessing ploughman.

his ground for any length of time, the adranThe inconveniences of ridges high and crook- tages that he will reap from having level and ed are so many that one would be tempted to well laid out fields are so considerable as to be apply a remedy at any risk. And yet, if the soil worth purchasing, if it should even be at a be clay, it would not be advisable for a tenant to considerable expense. But the loss that is susapply the remedy upon a lease shorter than too tained at the beginning by this mechanical mode nineteen years. In a dry gravelly soil, the work of levelling ridges, if they are of considerable is not difficult or hazardous. When the ridges height, is so very great, that it is doubtful if any are cleaved two or three years successively in the future advantages can fully compensate it. I course of cropping, the operation ought to be would therefore advise that all this levelling concluded in one summer. The earth, by reite- apparatus should be laid aside, and the followrated ploughings, should be accumulated upon ing more efficacious practice be substituted in the furrows, so as to raise them higher than the its stead : a practice that I have long followed crowns; they cannot be raised too high, for the with success, and can safely recommend as the accumulated earth will subside by its own weight. very best that has yet come to my knowledge. Cross ploughing, once or twice, will reduce the If the ridges have been raised to a very great ground to a flat surface, and give opportunity to height, as a preparation for the ensuing operaform ridges at will. The same method brings tions, they may be first cloven, or scalded out, down ridges in clay soil; only let the work be as it is called, that is, ploughed so as to lay the carried on with expedition ; because a hearty earth on each ridge from the middle towards shower, before the new ridges are formed, would the furrows; but, if they are only of a moderate soak the ground in water, and make the farmer degree of beight, this operation may be omitted. suspend the work for the remainder of that year When you mean to proceed to level the ground, at least. In a strong clay, the ridges should not let a number of men be collected, with spades, be altered, unless it can be done to perfection in more or fewer as the nature of the ground requires, one season. On this subject Dr. Anderson has and then set a plough to draw a furrow directly said, The difficulty of performing this operation across the ridges of the whole field intended to properly with the common implements of hus- be levelled. Divide this line into as many parts bandry, and the obvious benefit that accrues to as you have laborers, allotting to each one ridge the farmer from having his fields level, has pro- or two, more or less, according to their number, duced many new inventions of ploughs, harrows, height, and other circumstances. Let each of drags, &c., calculated for speedily reducing the the laborers, as soon as the plough has passed fields to that state; none of which have as yet that part assigned him, begin to dig in the botbeen found fully to answer the purpose for which tom of the furrow that the plough has just made, they were intended, as they all indiscriminately about the middle of the side of the old ridge, carry the earth that was on the high places into keeping his face towards the old furrow, workthose that were lower; which, although it may, ing backwards till he comes to the height of the in some cases, render the surface of the ground ridge, and then turn towards the other furrow, tolerably smooth and level, is usually attended and repeat the same on the other side of the with inconveniences far greater, for a considera- ridge, always throwing the earth that he digs up ble length of time, than that which it was intend- into the deep old furrow between the ridges ed to remove. For experience sufficiently shows that is directly before him; taking care not to that even the best vegetable mould, if buried for dig deep where he first begins, but to go deeper any length of time so far beneath the surface as and deeper as he advances to the height of the to be deprived of the benign influences of the at- ridge, so as to leave the bottom of the trench mosphere, becomes an inert lifeless mass, little he thus makes across the ridge entirely level, fitted for nourishing vegetables; and constitutes or as nearly so as possible. And when he bas a soil very improper for the purposes of the far- finished that part of the furrow allotted to him mer. It therefore behoves him to preserve, on that the plough has made in going, let him then every part of his fields, an equal covering of that finish in the same manner his own portion of vegetable mould that has long been uppermost, the furrow that the plough makes in returning. and rendered fertile by the meliorating influence In this manner each man performs his own task of the atmosphere. But if he suddenly levels through the whole field, gradually raising the old bis high ridges, by any of these mechanical con- furrows as the old heights are depressed. And trivances, he buries all the good mould that was if an attentive overseer is at hand, to see that on the top of the ridges in the old furrows, by the whole is equally well done, and that each which he greatly impoverishes one part of his furrow is raised to a greater height than the field, while he too much enriches another, and middle of the old ridges, so as to allow for the he has the mortification frequently to see the one subsiding of that loose earth, the operation will half of his crop rotted by an over-luxuriance, be entirely finished at once, and never again while other parts of it are weak and sickly, or need to be repeated. one part ripe and ready for reaping, while the In performing this operation, it will always other is not properly filled.

be proper to make the ridges formed for the purpose of levelling, which go across the old them, and plougning round and round till the ridges, as broad as possible; because the deep two ridges be finished. By this method, the setrench that is thus made in each of the furrows parating furrow is raised a little higher than the is an impediment in the future operations, as furrows that bound the two ridges. But at the well as the beight that is accumulated in the next ploughing that inequality is corrected, by be. middle of each of these ridges; so that the ginning at the bounding furrows, and going round fewer there are of these the better. The farmer, and round till the ploughing of the two ridges be therefore, will do well to advert to this, and completed at the separating furrow. begin by forming a ridge by always turning the For cleaning the ground of weeds, a cleaning plough to the right hand, till it becomes of such harrow is often used. It is drawn by a single breadth as makes it very inconvenient to turn horse, directed by reins, which the man at the longer in that manner; and then, at the distance opposite corner puts over his head, to have both of twice the breadth of this new-formed ridge hands free. In this corner is fixed a rope, with from the middle of it, mark off a furrow for the which the man from time to time raises the harmiddle of another ridge, turning round it to the row from the ground, to let the weeds drop. Por right hand, till it becomes of the same breadth, the sake of expedition, the weeds ought to be and then, turning to the left hand, plough out dropped in a straight line cross the field, whether the interval that was left between the two new- the harrow he full or not; and, seldom is a field formed ridges. By this mode of ploughing, so dirty but that the harrow may go thirty yards each ridge may be made of forty, or fifty, or sixty before the teeth are filled. The weeds will be yards in breadth, without any great inconvé- thus laid in parallel rows, like those of hay raked nience; for, although some time will be lost in 'together for drying. A harrow may be drawn turning at the ends of these broad ridges, yet, as swiftly along the rows, to shake out all the dust ; this operation is only to be once performed in and then the weeds may be carried clean off the this manner, the advantage that is reaped by having field in carts. But, instead of burning them, few open furrows is more than sufficient to coun they may be converted into useful manure, by terbalance it. To moderate the height that ould laying them in a heap, with a mixture of hot be formed in the middle of each of these great dung to begin fermentation. At first view, this ridges, it will be proper to mark out the ridges, .way of cleaning land will appear operose; but and draw the furrow that is to be the middle neither the labor nor expense is imtroderate. of each some days before you collect your la- At any rate, these ought not to be grudged; for, borers to level the field, that you may, without if a fieid be once thoroughly cleaned, the seasons any hurry or loss of labor, clear out a good must be very cross, or the farmer very indolent, trench through the middle of each of the old to make it necessary to renew the operation in ridges; as the plough at this time, going and less than twenty years. In the worst seasons a returning nearly in the same track, prevents the few years' pasture is always under command; laborers from working properly without this which effectually destroys triennial plants, such precaution. If these rules are attended to, your as thistles and couch-grass. field will be at once reduced to a proper level, 3. We may here offer a few remarks of a pracand the rich earth that formed the surface of the tical kind on soils : i. Clay is in general the old ridge be still kept upon the surface of your stiffest of all soils, and contains an unctuous field; so that the only loss that the possessor of quality. See Clay. But, under the term clays, such ground can sustain by this operation is earths of different sorts and colors are included. merely the expense of performing it.'

One kind is so obstinate that scarcely any thing Dr. Anderson afterwards makes a calculation will subdue it; another is so hungry and poor of the different expenses of levelling by the that it absorbs whatever is applied, and turns it plough and by the spade, in which he finds the into its own quality. Some clays are fatter than latter by far the cheapest method. It should be others, and the fattest are the best; some are a rule, according to him, to direct the ridges more soft and slippery. But all of them retain north and south if the ground will permit. In water poured on their surfaces, where it stagnates, this direction, the east and west sides of the and chills the plants, without sinking into the ridges, dividing the sun equally between them, soil. The closeness of clay prevents the roots will ripen at the same time. It is a great ad- and fibres of plants from spreading in search of vantage to form ridges só narrow and so low as nourishment. The blue, the red, and the white to admit the crowns and furrows to be changed clay, if strong, are unfavorable to vegetation. alternately every crop. The soil nearest the The stony and looser sort are less so; but none surface is the best; and, by such ploughing, it of them are worth any thing till their texture is is always kept near the surface, and never buried. so loosened by a mixture of other substances, and In high ridges the soil is accumulated at the opened, as to admit the influence of the sun, the crown, and the furrows left bare. Such altera- air, and frost. Among the manures recommended tion of crown and furrow is easy, where the for clay, sand is of all others to be preferred : ridges are only seven or eight feet broad. This and sea-sand the best of all, as it most effectually mode of ploughing answers perfectly well in breaks the cohesion. It is preferred, because it sandy and gravelly soils, and even in loam ; but is not formed wholly of small stones; but conit is not safe in clay soil. In that soil the ridges tains a great deal of calcareous matter, such as, ought to be twelve feet wide, and twenty inches shells grated and broken to pieces by the tide ; high; to be preserved always in the same form and al so salts. The smaller the sand is the by casting, that is, by ploughing two ridges to more easily it penetrates the clay ; but it abides gether, beginning at the furrow that separates less time in it than the larger The next best

VOL. XIX.

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