at most, only 20 parts in 100 of sand, is very stiff and crude, and cannot be tilled without great difficulty, unless its defects are corrected by a considerable admixture of humus and lime. Its quality, however, depends in a great measure upon the nature of the clay, and the quantity of silica which enters into its composition; such a soil is less defective if, while it contains only a small portion of sand, it possesses a large quantity of silica. When this argillaceous land does not contain sufficient humus to enable it to bear wheat without being manured afresh, and consequently cannot be entered in the first class, it will be termed wheat land of the second quality, or second-rate wheat land; but then it must not be totally destitute of humus. On rising grounds or eminences, we seldom find land, submitted to ordinary cultivation, which contains more than 3 parts in 100 of this compound matter; nevertheless, this land is well adapted for wheat, and that species of cereals succeeds much better, and with less trouble, than rye. Next to wheat, barley thrives best there, if the soil contains from 30 to 40 parts in 100 of sand; but when it only contains a smaller proportion, and this defect is not remedied by a strong admixture of lime, it is better adapted for oats. Such land is also exceedingly proper for the growth of vegetables, provided that it is sufficiently ameliorated. That which contains most sand is favorable to peas; while a stiffer and more tenacious soil grows beans with greater advantage. "The value of land diminishes in exact proportion with the decrease in the quantity of the sand contained in it, unless it belongs to the class of marly or calcareous soils, or to those which are strongly impregnated with humus. Thus, a soil containing 40 parts in 100 of sand is of the greatest value, while that which contains but 5 parts in 100 is much less esteemed. A tenacious and argillaceous soil, which is plentifully manured, and situated where an alternately hot and moist temperature not only favors the operations of ploughing and fallowing, but the processes of vegetation, is sometimes very superior, especially for the growth of wheat; but if we come to consider the difficulty there is in cultivating it, and how much more uncertain and casual the crops are there than they would be on a lighter soil, there can no longer be any doubt as to its inferiority in value. I estimate land which contains 2 parts in 100 of natural humus, 40 of sand, and about 60 of pure clay, at 70; that which only contains 30 parts in 100 of sand, at 60; that which contains but 20 parts, at 50; that which contains only 10 parts, at 40. Should it not possess more than 1 in 100 of humus, its value is decreased at least 20 per cent. Thus, tenacious soil, with little or no mild soluble humus, and which is usually termed cold, damp land, is actually one of the most steril that possibly can be; and may, in point of value, be assimilated to sandy land. On the other hand, its value is increased in proportion to the quantity of humus and clay which it contains; and such land may even be good enough to be entered in the first class, when it can be abundantly manured and properly tilled. "Land which contains more than 40, or from that to 60 parts in 100 of sand, is usually designated clay or potter's earth; but the less the proportion of sand falls below 40 parts in 100, the greater is the value of the land, supposing it to possess an equal quantity of humus. Where the proportion of sand does not exceed 50 parts in 100, the soil is equally adapted for the production of wheat and barley. But when that proportion increases from 50 to 60 parts in 100, wheat certainly may be grown there, provided the soil is properly cultivated; but the crops are never very fine or very abun dant, and the land is much more impoverished than it would have been if cropped with rye. Such a soil is, however, peculiarly well adapted for barley, and may be classed among the very best of those lands which are destined to bear this kind of grain. "The inherent advantages of a soil of this nature, (viz: of causing the crops to be less casual and uncertain, being more easily worked and tilled, preserving a moderate degree of temperature and humidity, &c.,) render it so very superior to argillaceous land, that, notwithstanding, its being less adapted to wheat, it may be assimilated to wheat land in all its gradations. In this case, the gradations are in an exactly inverse direction; 40 parts in 100 of sand appearing to us to be the best proportion. In the former case, the value.of the soil decreases when the proportion of sand diminishes; in the latter, on the contrary, the value decreases when the proportion is increased, but not in the same ratio. "From the observations which we have hitherto been able to make, the value of the soil appears to be almost equal in the following opposite proportions: Sand. Pure clay. "That is to say, the former are defective on account of their want of consistence, and the latter on account of their too great tenacity. "This kind of land may be vigorously tilled without becoming pulverized; neither does it harden into clods and furrows. It is seldom injured by an excess of moisture, and yet preserves sufficient humidity to enable it to resist the effects of drought for a considerable period; and young plants suffer much less in it than in tenacious soils, because their roots are better able to extend in all directions and penetrate it; and this is the reason that barley succeeds and flourishes so much better here. Such land will doubtless only bear fine crops of wheat when it has been thoroughly ameliorated; but when in a less fertile condition, it produces finer crops of rye than are grown on more argillaceous lands. It is also peculiarly adapted for vegetables, as potatoes and radishes; for clover and other kinds of fodder; and for plants of commerce, as cabbage, linseed, tobacco, &c., the cultivation of which is easy. It seldom offers any opposition to the action of the plough and harrow; and on this account, though it does not yield fine or large crops of wheat even in favorable years, it ought, in the gradations pointed out, to be assimilated to wheat land, properly so called. "Sand is injurious when it enters too largely into the composition of the soil: 1st. Because it is not sufficiently retentive of moisture, but it allows the water to evaporate or drain away, and carry with it the fertilizing particles and juices. 2d. Because it does not combine with the humus, and hardly enters into a physical union with it sufficiently strong to absorb those fertilizing particles which the atmosphere contains. 3d. Because sandy soils will not bear frequent cultivation, although constant tillage is necessary, in order to destroy the weeds which multiply so rapidly in land of this nature, especially when it contains a fair quantity of humus; and because these repeated workings deprive it of every particle of coherence, and, instead of ameliorating, tend rather to impoverish it, by bringing to the surface all that humus which was amassed in the interstices without being " " sad thus exposing it to the action of the atmosh rapidly decomposes and carries it away. 4th. good conductors of calorie, they transmit the inintense heat immediately to plants, at each sudemperature of the atmosphere undergoes. as more than from 60 to 80 parts in 100 of sand is The value of this land diminishes in proportion as the hat which contains 60 parts in 100 be valued at 60, parts ought not to be estimated at more than 50: 70 Value to 40; 75 parts to 30; and, lastly, that which Na 20. Wheat crops cannot be reckoned upon here, with sertany; and if the land contains 70 parts in 100 of sand, acapted to the production of this kind of grain, unless it be o a pecudar enriching course of tillage; but it is well calculated x.cularly when the situation is favorable, and the summers are ... iieastly worked or tilled, but is more liable to be overrun and ཧཱུྃ་་་་ སོ、 weeds than argillaceous soils. It has no great degree of coaccion for manure; but, on the contrary, rapidly decomposes that end allows it pass into the plants which vegetate there. This www xxx dhe të koqiring frequent manurings, although these need not be When rich and abundant ameliorations are bestowed upon i will become very rich in humus, and eventually be rendered ..、、、、 cortile, but this fertility rapidly declines, if the soil is submitted སྙི་རིས Laaxting totation. 5 contams 73 parts in 100 more of sand, it is usually designated oat evertheless, if we take the average of several years, we shall see xate proper for barley than for oats, provided it be sufficiently A soul which contains more than 80 parts in 100 of sand is called sandy and at the proportion of this substance does not exceed 90, it is disaced by the terim clayey sand. Usually, so long as land does not con1. o than 85 parts in too of sand, it is comprised in the class of oat nevertheless, the success of this grain is by no means certain, and it vicis hule or no produce, Rye and buckwheat are the only kinds of which it bears with any degree of success; and if it has been amey it is always better to sow successive crops of rye, than to sow oats ve, because the dryness to which this soil is exposed during the sumprejudicial to rye than to oats. Of all the plants or vegetables gown for the purposes of feeding cattle, potatoes have been culvw the greatest success on this sort of land. e dequent ploughings which, when this land is in good condition, wowed upon it, in order to cleanse it from weeds, are apt to render and thable that not any of the cereals can be made to succeed on it. season that it is advisable to allow it a certain repose, or to lay it away karannal pasture; and this latter is the means by which the greatest 4x4mage can be derived from it; for when sown with sheep's vachieve verna,) rye grass, (lolium perenne,) Dutch clover, vx common burnet, (poterium sanguisorba,) &c., it procock paxes age which is exceedingly well calculated for sheep, although ........'ỷ xà ferently wet for cattle. " a sprand of pasturage or repose, the land may be cultivated 4 wa with rye, yield very fine crops. "The value of it decreases in the ratio of 1 for every 100 in which the proportion of sand increases; and this diminution takes place even when the land contains from 1 to 14 part in 100 of humus; and if, as sometimes happens, it contains a yet smaller proportion, its value is still less. "But if the land contains 90 parts in 100 of sand, it then belongs to a still lower class. Unless it is properly mamured, nor until after a long period of repose, can it be made to bear a crop of cereals with any degree of advantage; and then this crop impoverishes it very much. Land which does not contain more than 94 parts in 100 of sand may, if properly managed, and sown with the small varieties of the festucas and vernal grass, be made to yield herbage enough to feed one sheep per acre during the period of repose. But when the soil contains a yet larger portion of sand, it will only bear gray-hair grass, (aria canescens,) yellow goats-beard, (tragopogon pratensis,) and some other plants which contain scarcely any nutritive juices. It then falls into the class of loose, blowing sands, the surface of which it is very dangerous to break, because then the wind moves it, and carries it away in whirlwinds. It may be regarded as an invariable rule, that sandy soil loses at least 1 part in 100 of its value by the augmentation of a hundredth part in the proportion of sand; and when it degenerates into loose, blowing sand, it possesses a mere negative value in by far the greater number of cases." * * * * While lime has produced such astonishing improvements in the crops, it must not be forgotten that it is at the expense of the earthy exhaustion of the humus, so necessary for vegetation; and hence the absolute necessity of manuring the land, in order to restore what is taken away. Without this precaution, barrenness will ensue. Some soils already contain too much lime. On this point, Mr. Thaer's remarks are worthy of attention. "That proportion of lime in land, which is most advantageous to it, is a quantity equal to pure clay. Of all the fifty-three varieties of soils produced by artificial combinations experimented on by Tillet, that which appeared to be most favorable to the vegetation of grain was composed of three-eighths of potter's clay, four-eighths of shell or fossil marl, and oneeighth of sand. "The more lime a soil contains, the less sand is required to correct the defects of the clay. But it is highly necessary that some portion of sand should enter into the combination; for, without that substance, marl, when dry, would be too tenacious, and, when moistened, too soft. General experience confirms the fact, that the proportions indicated by Tillet certainly are the best. "But even when lime is mingled with the superíor layer of the soil, in so small a quantity that it scarcely appears to have an influence on its consistence, it increases its fertility probably by means of the chemical action which it enters into with the humus and manure. From general experiments and observations, (which, nevertheless, cannot be very correct,) it appears that 10 parts in 100 of lime raise the value of argillaceous or clayey soils from 5 to 10 per cent., and even higher, when the land contains a large portion of humus. "On the other hand, lime is injurious when the proportion of it contained in the soil exceeds that of the clay. When the lime is mingled with much sand, it forms a soil too dry and warm, and which, even when plentifully manured, cannot be made to yield good crops of any thing but those vegetables which cannot be materially injured by drought-as maize, &c. Chaiky soils, which are principally composed of lime, are of this nature, and suffer both from drought and humidity; becoming, in the latter case, sloughy. "When speaking of the soils in which humus forms the chief component part, and in which this substante cannot be easily exhausted, we allude to those which contain more than 5 parts of it in 100. Such is only the case, however, in alluvial soils, or those which are formed by the deposite of rivers or of the sea. High grounds and mountainous districts-both those which contain a large portion of clay, and those in which sand is the preponderating ingredient-rarely possess 5 parts in 100 of humus; indeed, they seldom contain more than 3 parts of mild humus, especially at the close of a rotation, when they almost always require fresh manuring, in order to enable them to yield profitable crops. The quantity of humus contained in a soil diminishes in exact proportion with the number and condition of the crops derived from it; allowance, however, being made for the manure which it receives. This diminution is not, however, so considerable as it appears, or might be expected to be.” * "The tenacity and degree of cohesion existing between the parts of a soil can be best ascertained by examining it eight-and-forty hours after a gentle rain. Those who are accustomed to observation can ascertain all they wish to know upon this point by merely driving a stick into the soil, and sometimes even by simply pressing a foot upon it. "In forming an estimate of the value of a soil, an examination of its depth should folow immediately after an examination of its constituent parts. By the depth of a soil, I mean the thickness of a layer of earth which forms ne surface the layer which is usually termed vegetable earth, and which is homogeneous, and equally impregnated with humus throughout its whole extent. In most land, it descends very little below the depth of that layer which has been recently removed by the plough. When a section is cat vertically, the line of demarcation between the vegetable earth and the e-bool) is very apparent. Sometimes this layer is not more than three imenes deep; but the usual depth is about six inches, and it someLizzes extends ten or twelve inches below the surface. It is only in those paces where the soil has been amassed and deposited by the action of water, or when an extraordinary system of cultivation has been carried on, that we find the sol equally impregnated with humus to the depth of one, two, or three feet: s.x inches may, we think, be regarded as the average of the wi!. We shall therefore consider that, in order to be exempt from defects, and to be equal to the value which an investigation of its constituent parts leads us to give it, a sol must possess this depth or thickness. "A deep sol contains a larger portion of vegetable earth, and of that sucevleney so necessary to the nutrition of vegetables: and even if this excess of regetable mould should not be useful to all plants, it agrees with some of them, even when the whole depth of the soil is not turned up. And, besides, this thickness of the superior layer of his land enables a skilful nusbandman to draw at will upon the riches which it contains, and occasionally, or about once in six or seven years, to turn it all up, and profit by the stores of succulency and nutrition which the under part of it will yield. The roots of all plants sown in a soil of this nature-even those of the tribe of cereals-penetrate in a right line, and seek that nutriment at a greater depth, which they would otherwise have had to extend themselves laterally in |