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modification establish its use for this purpose, I" original soil." [Sinclair's Code of Agriculture would call this earth calz-and from it derive calx- - Chap. 1.] ing, to signify the application of calcareous earth, "The word loam should be limited to soils conin any form, as manure. A general and definite "taining at least one-third of impalpable earthy term for this operation is much wanting. Liming," matter, copiously effervescing with acids." [Damarling, applying drawn ashes, or the rubbish of vy's Agricultural Chemistry-Lecture 4.] Acold buildings, chalk, or limestone gravel-all these cording to this definition by the most scientific operations are in part, and some of them entirely, writer and highest authority in chemical agriculthat manuring that I would thus call calring. But ture, if we except the small portion of shelly land, because their names are different, so are their ef- there is certainly not an acre of natural loam befects generally considered-not only in those re-tween the sea coast of Virginia and the Blue spects where differences really exist, but in those Ridge Mountains-and very few, if any, even where they are precisely alike. in the limestone region.

[NOTE B. Page 11.]

THE NAMES GIVEN TO SOILS BY WRITERS ON
AGRICULTURE OFTEN INCORRECT AND
CONTRADICTORY.

Nothing is more wanting in the science of agriculture, than a correct nomenclature of soils, by which the characters might be learned from the names-and nothing has hitherto seemed less attainable. The modes of classing and naming soils, used by scientific authors, are not only different, and opposed to each other-but each one of them is quite unfit to serve the purpose intended. As to the crowd of inferior writers, it is enough to say that their terms are not fixed by any ruleconvey no precise meaning, and are worth not much more than those in common use among ourselves, and other practical cultivators, which often vary in their meaning within forty miles of distance. To enable us to judge of the fitness of the names given to soils by others, let us examine those applied by ourselves. We generally describe soils by making a mental comparison with those we are most accustomed to; and though such a description is understood well enough through a particular district, it may have quite a different meaning elsewhere. What are called clay or stiff soils in Sussex and Southampton, would be considered sandy or light soils in Goochland-merely because almost every acre of land in the former counties is sandy, and in the latter, clays are nearly as abundant.

The conflict of definitions, and consequent confusion of terms, cannot be more plainly set forth, than by quoting from some of the highest authorities, the various and contradictory explanations of a term, which is so common, that it is used by every one who writes or speaks of soils-and which, in some one or other sense, each writer probably considered as forming a very large, if not the greatest proportion of the cultivated soils of his country, and of the world.

"By loam is meant any of the earths combined "with decayed animal or vegetable matter." [Appendix to Agr. Chem. by George Sinclair.]

"Loam-fat unctuous earth-marl.” [Johnson's Dictionary, 8vo. Ed., and also Walker's.]

"Loam may be considered a clay of loose or "friable consistency, mixed with mica or isinglass, "and iron ochre." [Editor of American Farmer, Vol. III, page 320.]

[NOTE C. Page 13.]

SOME OF THE EFFECTS OF SLAVERY ON AG-
RICULTURAL PROFITS.

The cultivators of Eastern Virginia derive a portion of their income from a source quite distinct from their tillage-and which, though it often forces them to persist in their profitless farming, yet also, in some measure, conceals, and is generally supposed to compensate for its losses. This source of income is, the breeding and selling of slaves-of which, (though the discussion of this point will not be undertaken here,) I cannot concur in the general opinion that it is also a source of profit.

It is not meant to convey the idea that any person undertakes as a regular business the breeding of slaves with a view to their sale: but whether it is intended or not, all of us, without exception, are acting some part in aid of a general system, which taken altogether, is precisely what I have named. No man is so inhuman as to breed and raise slaves, to sell off a certain proportion regularly, as a western drover does with his herds of cattle. But sooner or later the general result is the same. Sales may be made voluntarily, or by the sheriff-they may be met by the first owner, or delayed until the succession of his heirs-or the misfortune of being sold may fall on one parcel of slaves, instead of another: but all these are but different ways of arriving at the same general and inevitable result. With plenty of wholesome, though coarse food, and under such mild treatment as our slaves usually experience, they have every inducement and facility to increase their numbers with all possible rapidity, without any opposing check, either prudential, moral, or physical. These several checks to the increase of population operate more or less on all free persons, whether rich or poor-and slaves, situated as ours are, perhaps are placed "Loam, or that species of artificial soil, into which the only possible circumstances, in which no re"the others are generally brought by the course straint whatever prevents the propagation and in"of long cultivation."-"Where a soil is mode- crease of the race. From the general ex"rately cohesive, less tenacious than clay, and ence of this state of circumstances, the particu r "more so than sand, it is known by the name of effects may be naturally deduced: and facts co"loam. From its frequency, there is reason to pletely accord with what those circumstances pro"suppose that in some cases it might be called an mise. A gang of slaves on a farm will often in

"Loam denotes any soil moderately cohesive, " and more so than loose chalk. By the author of "the Body of Agriculture, it is said to be a clay "mixed with sand." [Kirwan on Manures Chap. 1.]

crease to four times their original number, in thirty ly that calcareous earth is present in all soils-but or forty years. If a farmer is only able to feed its being always named as one of the ingredients and maintain his slaves, their increase in value of soils in general, and no cases of its absolute demay double the whole of his capital originally vested ficiency being directly stated, amount to the declain farming, before he closes the term of an ordinary ration that calcareous earth is very rarely, if ever, life. But few farms are able to support this increas- entirely wanting in any soil. We may find enough ing expense, and also furnish the necessary supplies directions to apply calcareous manures to soils that to the family of the owner-whence very many are deficient in that ingredient: but that deficiency, owners of large estates in lands and negroes, are seems to be not spoken of as absolute, but relative throughout their lives too poor to enjoy the com- to other soils more abundantly supplied. In the forts of wealth, or to encounter the expenses ne- same manner, they direct clay, or sand, to be used cessary to improve their unprofitable farming. A as manure for soils very deficient in one or the man so situated, may be said to be a slave to his other of those earths-but without meaning that own slaves. If the owner is industrious and fru-any soil under cultivation, can be found entirely gal, he may be able to support the increasing num-destitute of sand, or of clay. My proofs from ge-. ber of his slaves, and to bequeath them undimin-neral treatises, would therefore be generally indiished to his children. But the income of few per-rect-and the quotations necessary to exhibit them, sons increases as fast as their slaves-and if not, would show what had not been said, rather than the consequence must be, that some of them will what had that they did not assert the absence of be sold, that the others may be supported; and the calcareous earth, instead of directly asserting its sale of more is perhaps afterwards compelled, to universal presence. Extracts for this purpose, pay debts incurred in striving to put off that dread- however satisfactory, would necessarily be too voed alternative. The slave first almost starves his luminous, and it is well that they can be dispensed master, and at last, is eaten by him-at least he is with. Better proof, because it is direct, and more exchanged for his value in food. The sale of concise, will be furnished by quoting the opinions slaves is always a severe trial to their owner. Ob- of a few agriculturists of our own country, who stacles are opposed to it, not only by sentiments of were extensively acquainted with European auhumanity, and of regard for those who have pass-thors, and have evidently drawn their opinions ed their lives in his service-but every feeling he has of false shame comes to aid; and such sales are generally postponed, until compelled by creditors, and are carried into effect by the sheriff, or by the administrator of the debtor. But when the sale finally takes place, its magnitude makes up for all previous delays. Do what we will, the surplus slaves must be sent out of a country which is not able to feed them: and these causes continue to supply the immense numbers that are annually sold and carried away from Lower Virginia, with- "Of six or eight substances, which chemists out even producing the political benefit of lessen-" have denominated earths, four are widely and ing the actual number remaining. Nothing can “abundantly diffused, and form the crust of our check this forced emigration of blacks, and the vol- "globe. These are silica, alumina, lime, and untary emigration of whites, except increased pro-"magnesia."-"In a pure or isolated state, these duction of food, obtained by enriching our lands," earths are wholly unproductive; but when deand the consequent increase of farming profits." composed and mixed, and to this mixture is No effect will more certainly follow its cause than" added the residuum of dead animal or vegetable this-that whenever our land is so improved as to "matter, they become fertile, and take the geproduce double its present supply of food, it will also "neral name of soils, and are again denominated have, and will retain, double its present amount of" after the earth that most abounds in their compopulation. The improving farmer who adds one" position respectively.hundred bushels of corn to the previous product of his country, effectually adds also to its population, as many persons as his increase of product will

feed.

[NOTE D. Page 17.]

OPINIONS THAT SOILS ARE GENERALLY CAL-
CAREOUS.

from those sources. These quotations will not only show conclusively, that their authors consider the received European doctrine to be that all soils are more or less calcareous-but also, that they apply the same general character to the soils of the United States, without expressing a doubt or naming an exception.

1st. From a "Treatise on Agriculture," (ascribed to General Armstrong,) published in the American Farmer. [Vol. I. page 153.]

2.

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Address of R. H. Rose to the Agricultural Society of Susquehanna. [Am. Far. Vol. II. p.

101.]

"Geologists suppose our earth to have been masses of rock of various kinds, but principally "silicious, aluminous, calcareous, and magnesian "-from the gradual attrition, decay, and mixture "of which, together with an addition of vege"table and animal matter, is formed the soil; and "this is called sandy, clayey, calcareous, or mag"nesian, according as the particular primitive ma"terial preponderates in its formation."

It was asserted that the inference to be drawn 3. Address of Robert Smith to the Maryland from all the descriptions of soils, in the most es- Agricultural Society. [Am. Far. Vol. III. p. 228.] teemed treatises on agriculture, is that calcareous -The soils of our country are in general earth is a very general, if not a universal ingre- "clay, sand, gravel, clayey loam, sandy loam, dient. This assertion can be proved beyond all" and gravelly loam. Clay, sand, and gravel, doubt, from European authors: but it would re- "need no description, &c."-" Clayey loam is a quire many and long extracts, too bulky to include "compound soil, consisting of clay, and sand or ere, and which cannot be fairly abridged, or ex- gravel, with a mixture of calcareous matter, and habited by a few examples. No author says direct-" in which clay is predominant. Sandy, or gra

"velly loam, is a compound soil, consisting of "sand or gravel, and clay, with a mixture of cal"careous matter, and in which sand or gravel is "predominant."

[NOTE E. Page 18.]

DIRECTIONS FOR ANALYZING MARL, AND
OTHER CALCAREOUS SUBSTANCES.

Davy's apparatus for measuring the carbonic acid
It is unnecessary here to describe Professor
soil, (and of course of marl,) and thus ascertain-
gas evolved from any given quantity of calcareous
tained.
ing the proportion of the carbonate of lime con-
not be made plain-and the expense of the appa-
Without a plate, the description could
chase to every reader who cannot easily refer to
ratus would be a sufficient prohibition of the pur-
the original description in the Elements of Agri-
cultural Chemistry.

has used successfully, a much cheaper apparatus,
Prof. W. B. Rogers, has recently invented, and
and which for trials of very small quantities of marl,
is also much more correct.
apparatus will be copied from the Farmers' Re-
His description of this
gister, Vol. II. p. 364.

The first two extracts merely state the geological theory of the formation of soils, which is received as correct by the most eminent agriculturists of Europe. How far it may be supported or opposed by the actual constitution, and number of ingredients of European soils, is not for me to decide, nor is the consideration necessary to my subject. But the adoption of this general theory, by American writers, without excepting American soils, is an indirect, but complete application to them, of the same character and composition. The writer last quoted, states positively that the various loams, (which comprise at least nineteentwentieths of our soils, and I presume also of the soils of Maryland,) contain calcareous matter. The expression of this opinion by Mr. Smith, is sufficient to prove that such was the fair and plain deduction from his general reading on agriculture, from which source only could his opinions have been derived. If the soils of Maryland are not "The apparatus which I am about to describe, is very unlike those of Virginia, I will venture to as- intended to give greater accuracy and facility to sert, that not one in a thousand of all the clayey, the usual process for determining the quantity of sandy, and gravelly loams, contains the smallest carbonic acid in marl, or in any of the carbonates. proportion of carbonate of lime-and that not a By the common method, the two vessels containsingle specimen of calcareous soil can be found, ing severally the marl and the muriatic acid are between the falls of the rivers, and the most eas-placed in one of the scales of a delicate balance, tern body of limestone. and there counterpoised by weights put into the But though the direct testimony of European other scale. The acid is then poured upon the authors, (as cited in the essay,) concurs with the marl, and after all the carbonic acid has been disindirect proofs referred to in this note, to induce charged, the equilibrium is restored by adding the belief that soils are very rarely destitute of weights to one, or abstracting them from the other calcareous earth, yet statements may be found of scale. In principle, this method is entirely free some particular soils being considered of that cha- from objection: but as usually conducted, it cannot racter. These statements, even if presented by be relied upon as accurate. This want of precithe authors of general treatises, would only seem sion arises, in the first place, from the escape of to present exceptions to their general rule of the aqueous vapor, along with the carbonic acid which almost universal diffusion of calcareous earth in is discharged, thus making a greater weight nesoil. But so far as I know, no such exceptions cessary for restoring the equilibrium, than is due are named in the descriptions of soils in any gene- to the quantity of carbonic acid which has escaped ral treatise, and therefore have not the slightest and secondly, from the greater weight of the effect in contradicting or modifying their testimony vessels containing the marl and acid impairing on this subject. It is in the description of soils of the sensibility of the balance, and thus rendering particular farms, or districts, that some such state- it impossible to estimate the carbonic acid to small ments are made: and even if no such examples fractions of a grain. The first of these objections had been mentioned, they would not have been has long been obviated in the chemical analysis needed to prove the existence, in Europe, of some of the carbonates, by causing the gas, as it escapes, soils like most of ours, destitute of calcareous to pass through a tube containing dried muriate of earth. These facts do not oppose my argument. I lime; and the latter has been in some measure rehave not asserted, (nor believed, since I have en- moved, by a contrivance of the great practical deavored to investigate this subject,) that there chemist Rose; which, however, as it is inconvewere not soils, and perhaps many extensive dis-nient and uncertain in the manipulation, I shall not tricts, containing no calcareous earth. My argu- here describe. ment merely maintains that these facts would not be inferred, but the contrary, by any general and cursory reader of the agricultural treatises of Europe, that we are best acquainted with. It has not been my purpose to inquire as to the existence, ur extent, of soils of this kind in Europe. But judging from the indirect testimony furnished by accounts of the mineral and vegetable productions in general descriptions of different countries, I would suppose that soils having no calcareous earth were ofien found in Scotland and the northern part of Germany, and that they were comparaively rare in England and France.

"The apparatus which I have devised, is, I think, free from these objections, and enables the operator to proceed with great accuracy and despatch. It has the advantage of being very easily constructed, and of being used with a balance that can be procured at a very moderate price. Moreover, the quantity of marl which is necessary for experiment in no case exceeding ten grains, pecimens for analysis may very easily be forwarded by letter.

"The balance which I use with this apparatus, is a small goldsmith's balance-such as may be procured for a few dollars in New York. It is very light, and turns, when unloaded, with the th of a grain. My set of weights obtained from Mil

lington in Philadelphia, extends to tenths and hun- | in the 10 grains of marl-or almost precisely 66 dredths of the grain. per cent. "The accompanying figure will convey a distinct "The frequent calls upon me for the analysis of idea of the apparatus and mode of using it. One specimens of marl, first led me to the construcof the scales is removed to admit of suspending tion of this apparatus; and I have since found it the apparatus by a double thread over the hook of so convenient and accurate, that I can recommend the beam. The other is made of something light, its adoption to such of your readers as may have as a piece of card. In this way all unnecessary a taste for chemical inquiries connected with agweight upon the beam is avoided, and its sensi- riculture. Any ordinary worker in glass will conbility preserved. struct the instrument, and skill_in_manipulating with it may be soon and easily acquired.

B

"A, is a light bulb of glass, blown very thin from a common piece of tube, and about one inch in diameter. A cork is fitted to its mouth, and through this, the tapered ends of the bent glass tubes, B and C, are passed air tight; the extremity of the latter extending some distance into the vessel. The tube B, through which the gas escapes, is filled with fragments of muriate of lime. The tube C, which contains the muriatic acid, is furnished with a light piston of cork or cotton, in the centre of which is fixed a rod or handle, made of a small stiff straw. This instrument, when charged with marl and acid, does not weigh more than 120 grains. The whole load of the beam is therefore 240 grains, and it is still sensible to theth of a grain.

WM. B. ROGERS."

The principle upon which the apparatus works, is the same as that of the more expensive and complicated apparatus of Davy, (described in his Agricultural Chemistry) which I had previously considered the best-that is by separating and ascertaining the weight of the carbonic acid combined with the lime of the manure. Every hundred grains of calcareous earth or carbonate of lime, is composed always of similar proportions of lime and of carbonic acid-which proportions, by weight, are 56 parts of lime, and 44 of carbonic acid. Of course, if we know how much weight is lost in 100 grains of earth partly of carbonate of lime, (as marl,) by driving off its carbonic acid, the rule of proportion will show what was the amount of carbonate of lime contained in the sample of earth.

When the muriatic acid reaches the earth in the bulb, it immediately combines with the lime by its greater attraction, and the weaker (carbonic) acid is disengaged in the form of gas, and escapes into the air through the tube containing the dry muriate of lime-which substance attracts moisture so powerfully, as to retain all that might otherwise pass out with the gas. The same muriate of lime will serve for many experiments, as by being heated in the tube, its dryness is restored previous to every trial. This salt is formed by the combination of muriatic acid with lime-and therefore every experimenter may provide it for himself, by filtering and evaporating the fluid left in this process of decomposing carbonate of lime.

Mr. Rogers has since informed me that a small portion of dry and lightly carded cotton will serve as well as the muriate of lime for arresting the moisture.

"The mode of proceeding with the analysis is as follows. Five or ten grains of the finely powdered marl is introduced into the vessel A, and then two or three drops of water added, to assist the diffusion of the acid. The small end of the tube C, now removed from the cork, is dipped into some muriatic acid in a wine glass, and the piston moved backwards and forwards until the necessary quantity of acid has been drawn in. The tube is then replaced in the cork, and in this state the in- The mode of analyzing by solution and precipstrument is counterpoised by weights in the oppo-itation, though not to be trusted for operations site scale, The piston being then gradually forced where great exactness is required, and although in, the acid is injected, drop by drop, upon the marl, much more troublesome than the using of either and the gas escapes by the tube B, depositing the Davy's or Rogers' apparatus, is sufficiently coraqueous vapor in its passage, on the muriate of rect for testing the strength of marl: and it has lime. Allowing the apparatus to rest until the the advantage of requiring no apparatus, except gas has entirely escaped, and the decomposition is a glass funnel, some blotting paper, and a set of complete, the equilibrium is restored by placing small physic scales and weights-and no other weights upon the clear top of the cork, or by re- tests than muriatic acid and carbonate of potashmoving weights from the scale. In this way the all of which may be obtained at any apothecary's weight of the disengaged gas is accurately deter-shop. The directions which follow, will be given mined, and the proportion of carbonate of lime thence computed.

"An analysis of a specimen of mar! from James City, just completed, will serve as an illustration he method. Ten grains of the finely powdered man was introduced with a little water into the vesel A, the instrument was then charged and equipoised. The acid being injected, the whole was allowed to rest for an hour. The weight lost was 2.91 grains. Increasing this in the ratio of 14 to 100, gives 6.61 grains of carbonate of lime

with so much minuteness, that any attentive reader may both understand and follow them in practice, though totally unacquainted previously with chemical terms and processes. These directions also first appeared in the Farmers' Register, Vol. I. p. 609.

1st. Take a lump of marl, fossil shells, &c. large enough to furnish a fair sample of the particular body under consideration-dry it perfectly, near the fire-pound the whole to a coarse powder (in a metal mortar,) and mix the whole to

edly washed by pouring on water, then dried, scraped off, and weighed. This will be the actual proportion of the calcareous part of the sample, except, perhaps a loss of one or two grains in the hundred. The loss, therefore, in this part of the process apparently lessens, as the loss in the earlier part increases the statement of the strength of the manure. The whole may be supposed to stand thus

gether. Take from the mixture a small sample, cess,) the whole must be poured on another filterwhich reduce to a finely divided state, and weighing paper, and (as before,) the solid matter repeatof it a certain portion, say 50 grains, for trial. 2nd. To this known quantity in a glass, pour slowly and at different times, muriatic acid diluted with three or four times its bulk of water-(any except limestone, or hard water.) The acid will dissolve all the lime in the calcareous earth, and let loose the carbonic acid with which it was previously combined, in the form of gas, or air, which causes the effervescence, which so plainly marks the progress of such solution. The addition of the muriatic acid, must be continued as long as it produces effervescence; and but very little, after that effect has ceased. The mixture should be well and often stirred, and should have enough excess of acid to be sour after standing thirty or forty minutes. (So much of the acid as the lime combines with, loses its sour taste, as well as its other peculiar qualities.)

3rd. The mixture now consists of 1. the lime combined chemically with muriatic acid, forming muriate of lime, which is a salt, and which is dissolved in the water-2. a small excess of muriatic acid, mixed with the fluid-and 3. the sand, clay and any other insoluble parts of the sample of marl. To separate the solid from the fluid and soluble parts, is the next step required.

Take a piece of filtering or blotting paper, about six or eight inches square, (some spongy and unsized newspapers serve well,) fold it so as to fit within a glass funnel, which will act better if its inner surface is fluted. Pour water first into the filter, so as to see whether it is free from any hole, or defect-if the filtering paper operates well, throw out the water, and pour into it the whole mixture. The fluid will slowly pass through into a glass under the funnel, leaving on the filter all the solid parts, on which, water must be poured once or twice, so as to wash out, and convey to the solution, every remaining particle of the dissolved lime..

100

27 grains of sand and clay.
of carbonate of lime.
of loss.

21 2

=50.

If the loss be divided between the carbonate of lime and the other worthless parts of the manure, it will make the proportions 28 and 22, which will be probably near the actual proportions.

The foregoing method is not the most exact, but is sufficiently so, for practical use. All the errors to which it is liable, will not much affect the reported result-unless magnesia is present, and that is not often in manures of this nature. Magnesia is never found (I believe,) in the collections of fossil shells-nor have I known of its presence in any of the earthy manures, except limestone, and the magnesian marl lately discovered in Hanover. If any considerable proportion of carbonate of magnesia should be present in marl tried by the foregoing method, it may be suspected by the effervescence being very slow, compared to that of carbonate of lime alone: and the proportions of these two earths may be ascertained as follows. The magnesia as well as the lime would be dissolved by the muriatic acid, (applied as above directed,) but the magnesia would not be precipitated with the carbonate of lime, but would remain dissolved in the alkaline solution, last separated by filtering. If this liquor is poured into a Florence flask, and boiled for a quarter of an hour, the carbonate of magnesia will fall to the bottom, and may then be separated by filtering and washing, and its quantity ascertained, by being dried and weighed. This part of the process may be easily added to the foregoing—but it will very rarely be required."

4th. The solid matter left, after being thus washed, must be taken out of the funnel on the paper, and carefully and thoroughly dried-then scraped off the paper and weighed. The weight, say 27 grains, being deducted from the original If desired, the proportions of silicious and aluquantity, 50, would make the part dissolved (50-minous earth may be ascertained, with enough 27=23,) 46 of the whole. And such may be truth for practical use, by stirring well these parts taken as very nearly the proportion of calcareous (minutely divided,) in a glass of water, and after earth (or carbonate of lime) in the compound ex- letting it stand a minute, for the sand to subside, amined. But as there will necessarily be some pouring off the fluid into another glass. The loss in the process, and every grain taken from the sand will be left, and the aluminous earth, or pure solid parts, appears in the result as a grain added clay, pass off with the water-and each may be to the carbonate of lime, it will be right in such collected and dried on filtering paper, and weighed. partial trials to allow about two per cent. for loss, which allowance will reduce the foregoing statement to of carbonate of lime.

[NOTE F. Page 27.]

FURNISHED BY THE RECENT RESEARCHES

OF CHEMISTS.

5th. But it is not necessary to rely altogether on the estimate obtained by subtraction, as it may be proved by comparison with the next step of the PROOFS OF THE EXISTENCE OF ACID SOILS, process. Into the solution (and the washings) which passed through the filter, pour gradually a solution of carbonate of potash, (salts of tartar.) The first effect of the alkaline substance thus add- The Traité de Chimie is a French translation ed, will be to take up any excess of muriatic acid by Esslinger, of the voluminous and valuabje in the fluid-and next, to precipitate the lime work of the great Swedish chemist Berzens. (now converted again to carbonate of lime,) in a The original work and the French translation thick curd-like form. When the precipitation is were in the course of publication at the same time; ended, and the fluid retains a strong taste of the and the first volumes of the latter were publish carbonate of potash, (showing it to remain in ex-at Paris, before the latter volumes of the original

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