ANALYSIS. Analysis consists in determin ing the constituent, elements of the subject of analysis. By it we show either the organic or inorganic elements. In soils, for instance, we may find how much sand, lime, alumina, phos phoric acid, potash, magnesia and other constit uents are contained in the sample; but we can not through analysis at any definite de termination of the amount of plant food which is at the disposal of the present crop. It may or may not be locked up in insoluble forms.. Hence it has been found that experience alone must demonstrate the productions of the soil. But an analysis of a soil.may show its adaptation natur ally to certain crops. Here, again, experience is sufficient in the generality of cases. It is the fact that the chemist may compound a soil artificially containing every element of plant food in abund ance, and yet which will be perfectly • sterile, because locked up in insoluble combinations. Nitrogen, phosphoric acid, and potash, are the three important constituent elements in soils, because these are, as a rule, the substances whose absence or deficiency impair fertility. Yet there are many cases when lime, magnesia, oxide of iron, chlorine, sulphuric acid, etc , may be needed, because absent or deficient, and hence they become prime integers, Analysis will show the absence of a constituent, and hence its value, in special cases, when particular crops are to be raised, the soil, perhaps, lacking only one or two of the constituents necessary to perfect the crop. When we come to the plants or grains them selves, analysis becomes more practically im portant, since it shows just the amount of nutri tion contained. Thus, in special feeding, it becomes of -especial value to know the constit uents of certain foods. And in the feeding of calves, when skim milk or whey is to be used, analysis will show what should be added to either to form a comparatively perfect food. We say comparatively, for in combined food, how ever perfectly or scientifically it may be com it can not equal the whole and natural milk of the cow. This is the type of all animal food, milk being conceded to be practically as well as theoretically a perfect food. Several analyses of milk taken together we have averaged-as fol lows: Water 86.0 Flesh-formers 5.0 Fat-formers '8 0 Mineral matter 1.0 100 0 In the manufacture of butter the fat-formers are the principal constituent removed. Hence in practice,' the addition of linseed meal, or mush from finely ground Indian corn, or both, brings up the skimmed milk and buttermilk, relatively, to its normal condition as food for calves, after they are three or four weeks old. If the milk is converted into cheese, the flesh-formers are also removed. Hence the difficulty of bringing whey again to a perfect food. To do so, the equiva lent of the casein, albumen, etc., must be res tored. This may be measurably attained by the addition of oatmeal mush, and a little of lin seed cake. Economically, milk may be stated to contain the following constituents: Water 86.0 Casein 5.0 Fatty matter 3.5 Sugar 4.5 'Mineral matter 1.0 100.o The following table will show results of many analyses of various food substances, economic ally considered, in comparative equivalents: In relation to analyzing a soil, says Prof. Hitch- • cock, in his report of the Geological Survey of Massachusetts, Dr. Davy sets out by stating ,that geine constitutes thre basis of all the nourishing part of vegetable manures. - By the term geme, he means all the decomposed organic matter of the soil, chiefly derived from decayed vegetable matter. Animal substances, he says, produce a similar compound containing azote or nitrogen. There may be undecomposed vegetable fibres so minutely divided as to pass through the sieve, but as one object of this operation is to free the soil from vegetable fibre, the portion will be quite inconsiderable, and can only affect the amount of insoluble geine When so minutely divided, it will probably pass into soluble geine in a season's cultivation. Geine, or the vegetable nourishing matter of soils, exists in two states, in one of which it is soluble in water, etc , whilst in the insoluble state it resists the solvent power of water. Soluble geine he considers the im mediate food of growing plants, whilst insoluble . geine becomes food after sufficient exposure to air and, moisture. Hence the reason and result of tillage. We quote the following rules of analysis: 1. Sift the soil through a fine sieve. Take the fine part; bake it just up to browning paper. 2. Boil 100 grains of the baked soil, with 50 grains of pearl ashes, saleratus or carbonate of soda in four ounces of water, for half an hour; let it settle; decant the clear; wash the grounds with four ounces boiling water; throw all on a weighed filter, previously dried at the same temperature as was the soil (1); wash till colorless water _returns. Mix all these liquors. It is a brown-colored solution of all the soluble geine. All sulphates have been converted into carbonates, and with any phosphates, are on the ' filter. Dry therefore that, with its contents, at the same heat as before. Weigh—the loss is soluble geine. 3. If you wish to examine the geine; precipitate the alkaline solution with ex cess of lime-water. The geate of lime will rapidly subside, and if lime-water enough has been added, the nitrous liquor will be colorless. Col lect the geate of lime on a filter; wash with a little acetic or very dilute muriatic acid, and you have geine quite pure. Dry and weigh. 4. Re-' place on a funnel the filter (2) and ifs earthy contents; wash with two drachms muriatic acid, diluted with three times its bulk of cold water. Wash till tasteless. The carbonate and phos phate of lime will be dissolved with a little iron, which has resulted from the decomposition of any salts of iron, beside a little oxide of iron. The alumina will be scarcely touched. We may estimate all as salts of lime. Evaporate the uriatic solution to dryness, weigh and dissolve in boiling water. The insoluble will be phos phate of lime. Weigh—the loss is the sulphate of lime. (I make no allowance here for the dif ference in atomic weights of 'the acids, as the result is of no consequence in this analysis.) 5. The earthy residuum, if of a greyish white color, contains no insoluble geine—test it by burning a weighed small quantity on a hot shovel—if the odor of burning peat is given off, the presence of insoluble geine is indicated. If so, calcine the earthy residuum and its filter—the loss of weight will give the insoluble geine; that part which air and moisture, time and lime, will into nto soluble vegetable food. Any error
here will be due to the loss of water in a hydrate, if one be present, but these exist in too small quantities in granitic sand to affect the result. The actual weight of the residuary mass is gran itic sand. The clay, mica, quartz, etc., are easily distinguished. If your soil is calcareous— which may be easily tested by acids—then before proceeding to this analysis, boil 100 grains in a pint of water, filter and dry as before, the loss of weight is due to the sulphate of lime, even the sulphate of iron may be so considered; for the ultimate result in cultivation is to convert this into sulphate of lime. Test the soil with muriatic acid, and having thus removed the lime, proceed as before, to determine the geine and insoluble vegetable matter. In applying Dr. Dana's rules given in the text, to the soils of Massachusetts, I found it necessary to adopt some method of carrying forward several pro cesses together. I accordingly made ten com partments upon a table, each provided with apparatus for filtering and precipitations, also ten numbered flasks, ten evaporating dishes, and a piece of sheet-iron pierced with ten holes, for receiving the same number of crucibles. I pro vided, also, a sheet-iron oven, with a tin bottom large enough to admit ten filters, arranged in proper order, and a hole in the top to admit a thermometer. The sand bath was also made large enough for receiving the ten flasks. In this manner I was able to conduct ten processes with almost as great facility as one could have been carried forward in the usual way. As be fore stated, Dr. Dana regards geine as the basis of all the nourishing part of vegetable manures. The relation of soils to heat and moisture, he says, depend chiefly on geine. It is in fact, under its three states of vegetable extract, geine and carbonaceous mould, the principle which gives fertility to soils long after the action of common manures• has ceased. In these three states it is essentially the same. The experiments of Saus sure have long ago proved that air and moisture convert insoluble into soluble geine. Of all the problems to be solved by agricultural chemistry, none is of so great practical importance as the determination of the quantity of soluble and in soluble geine in soils. This is a question of much higher importance than the nature and proportions of the earthy constituents and sol uble salts of soils. It lies at the foundation of all successful cultivation. Its importance has been not so much overlooked as undervalued. Hence, on this point the least light has been reflected from the labors of Davy and Chaptal. It needs but a glance at any analysis of soils, published in the books, to see that fertility de pends not on the proportion of the earthy ingre dients. Among the few facts, best established in chemical agriculture, are these : that a soil, whose earthy part is composed wholly or chiefly of one earth ; or any soil with excess of salts, is always barren; and that plants grow equally well in all soils destitute of geine, up to the period of fructification,—failing of geine, the fruit fails, the plants die: Earths, and salts, and geine, constitute, then, all that is essential; and soils will be fertile, in proportion as the last is mixed with the first. The earths are the plates, the salts the seasoning, the geine the food of plants. The salts can be varied but very little in their proportions, without injury. The earths admit of wide variety in their nature and ,.proportions. I would resolve all into granitic sand; by which I mean the finely divided, almost impalpable mixture of the detritus of granite, gneiss, mica slate, sienite, and argillite; the last, giving by analysis, a compound very similar to the former. When we look at the analysis of vegetables, we find these inorganic principles constant constit uents—silica, lime, magnesia, oxide of iron, potash, soda, and sulphuric and phosphoric acids. Hence, these will 'be found constituents of all soils. The phosphates have been over looked from the known difficulty of detecting phosphoric acid. Phosphate of lime is so easily soluble when combined with or gela tine, that it is among the first principles of soils exhausted. Doubtless, the good effects, the last ing effects, of bone manure, depend more on the phosphate of lime, than on its animal portion. Though the same plants in different soils are found to yield variable quantities of the salts and earthy compounds, yet I believe that accurate analysis will show, that similar parts of the same species, at the same age, always contain the inorganic principles above named, when grown in soils arising from the decomposition of granite rocks. These substances will be found not only in constant quantity, but always in definite proportion to the vegetable portion of each plant. The effect of cultivation may depend, therefore, much more on the introduction of salts than has been gen erally supposed. The salts introduce new force. So long as the salts and earths exist in the soil, so long will they form voltaic batteries with the roots of growing plants, by which, the granitic sand is decomposed and the nascent earths, in this state readily soluble, are taken up by the absorbents of the roots, always a living, never a mechanical operation. Hence, so long as the soil A granitic,—using the term as above defined,—so. long is it as good as on the day of its deposition; salts and geine may vary, and must be modified by cultivation. The universal diffusion of gran itic diluvium will always afford e,nough of the earthy ingredients. The fertile character of soils, I persume, will not be found dependent on any partiCular rock formation on which it reposes. Modified they may be, to a certain extent, by peculiar formations; but all our granitic rocks afford, when decomposed, all those inorganic principles which plants demand. This is so true, that on this point the farmer already knows all that chemistry can teach him. Clay and sand, every one knows; a soil too sandy, too clayey, may be modified by mixture, but the best possi ble mixture does not give fertility. That de pends on salts and geine. If these views are correct, the few properties of geine which we have mentioned, will lead us at once to a simple and accurate mode of analyzing soils; a mode which determines at once the value of a soil, from its quantity of soluble and insoluble vegetable nutri ment; a mode requiring no array of apparatus, nor delicate experimental tact; one, which the country gentleman may apply with very great accuracy, and, with a little modification, per fectly within the reach of any man who can drive a team or hold a plow.