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and neisprison of treason against the State, and what punishment should be inflicted for those offences.

Indeed, in all legal matters, Mr. Ross at this period stood deser. vedly high. Before the revolution he was among the first of his profession, and in the change which that event had produced in its component parts, as well as its forensic character, he still maintained the same rank. These changes were indeed very considerable; subjer·t's of higher importance than those which commonly fall to the lot of provincial judicatures were brought forward; mo. tives sufficient to rouse all the latent energies of the mind were constantly presenting themselves. The bar was chiefly composed of gentlemen of aspiring minds, and industrious habits; and Mr. Ross found himself engaged among men, with whom it was honorable to contend and pleasant to associate. Mr. Wilson, who had practiced with great reputation at Carlisle; Mr. Biddle, from Reading; Gouverneur Morris, occasionally, and occasionally Mr. Read, till he was chosen a member of the chief executive council; Mr. Sergeant, who, in 1777, was appointed attorney general; and Mr. Lewis, of Philadelphia, in conjunction with Mr. Ross, formed an assemblage of powerful and splendid talents, which might have coped with an equal number of any forum in America. The whole faculties of this bar were soon put in requisition, by the prosecutions which were commenced against some of those accused of being adherents to the British cause. The popular excitement against them was high, and their defence appeared to many a service of danger; but the intrepidity of the bar did not allow them to shrink from the conflict, and Mr. Ross and Mr. Wilson especially embarked all their talents, zeal and professional reputation in the cause of those who were thus accused.

The last public employinent in which Mr. Ross was engaged, was that of a judge of the court of admiralty for the State of Pennsylvania, to which he was appointed on the fourteenth of April, 1779; and while on the bench he was esteemed a learned and impartial judge, displaying sound legal knowledge and abilities, and great promptness in his decisions. He did not, however, long occupy ihe station he was so well calculated to fill, as he died suddenly in the month of July following, from a violent attack of the gout.

of his character little remains to be said, beyond that which may be collected from the preceding pages; in his domestic habits he was kind, generous, and much beloved; in his professional career, zealous and honorable; as a politician always active and patriotic; and he seems to have well deserved the praise which was bestowed on him by one who knew him, as "an honest man and upright judge."--.American Biography.

AGRICULTURE.

From Chaptal's Agricultural Chymistry. MANURES.

[The nature and action of manures explained and illustrated by M. John Anthony Chaptal, Count of Chanteleup, Peer of France, member of the Institute, &c.]

(Concluded.) From the explanations to be continued, which I have given to the manner in which lime acts, we may draw some conclusions in regard to its uses, and the manner in which it should be employed in them, to have the results, arising from its application, conform to those which have been produced by enlightened experiments.

It is acknowledged that lime is principally useful upon fallow lands, which are broken up; upon grass lands, whether natural or artificial, which are prepared for cukivation; and upon muddy lands, which are to be put into a state fit for cultivation. It is well known, that in all these cases, there exists in the land a greater or less quantity of roots, which by the application of lime, may be made to serve more immediately for manure, by the solubility it will give to the products formed by them; but this effect can be produced neither by spreading the lime on the land, at the time of sowing the seed, nor by throwing it upon the soil without covering it, nor by sprinkling it upon the plants which have began to unfold; it is necessary to scatter it upon the land before the first tilling, and only as fast as it can be mixed with the soil, and place it in contact with the roots and stalks upon which it is to act, and at the end of some months this action is completed. · Independently of this effect, which in my opinion is the most important, lime exercises other powers, which make it a very valua. ble agent in agriculture. It cannot be denied, that the long existence and the barrenness of a marshy or turfy soil, give rise on such lands to myriads of insects, which repeated tillages, and frequent changes of crops can destroy only in a great length of time; whilst the mixture of lime with the earth performs the work immediately. It is certain that some plants which injure the soil and the crops, escape every tilling, but are immediately destroyed by the action of lime. It is clear, that to produce these effects, the lime must be applied in the caustic state. The mode of preparing it is as follows:

As lime absorbs water with avidity, exhaling vapor and producing noise and heat, and crumbling into pieces, that liquid may be thrown upon it, till the whole mass is reduced to a dry and impalpable powder; and it is in this state that it must be used.

In order to preserve the husbandman from the deleterious effects upon the lungs, of this light powder, it is best to mix it with some moistened earth; and in order that it may preserve all its virtue, it is necessary that it should be immediately buried in the soil by ploughing.

The custom of employing air-slacked lime, which is lime in the state of a sub-carbonate, is spreading in France every year and is productive of good results. This lime is, undoubtedly, less active ihan that which has been slacked by water; but it requires fewer precautions in the use of it, and is not liable to so many inconveniences.

When lime has been acted upon by the air, till it is reduced to the state of an impalpable powder, it is used with great advantage by mixing it with dung-hill manure; it serves to correct the acidity arising from the decomposition of certain portions of this, such as the marsh of grapes, &c., and absorbs the juices that would flow off and be lost, or would be too rapidly decomposed; it likewise fixes the juices, which would otherwise ascend into the atmosphere. This mixture spread upon the field excites vegetation, warms cold soils, divides those which are compact, regulates the fermentation of manures, and furnishes to plants gradually, and in proportion to their wants, the nutritive principles with which it is impregnated.

Lime slacked by air, does not entirely lose the property of being soluble in water, and when used, it is carried into the organs of plants by that liquid, producing those good effects, which arise from the employment of saline substances, in small quantities.

Limestone saturated with carbonic acid, though it may be reduced to powder, does not produce any of the good effects arising from the use of quick lime. M. Tennant obtained from 20 to 22 per cent. by throwing upon this mixture a little more nitric acid, diluted with water, ihan was necessary to saturate it; the liquor remained iurbid, and of a whitish color.

I have always observed, that all earths, of whatever natures containing magnesia, render thc waters covering them whitish, and that the agitation of these waters by the wind, takes from them all their transparency. When such waters are from ponds or pools, they are called white waters.

Magnesian earths possess but little fertility; and when the lime employed for agricultural purposes contains magnesia, its beneficial effects do not follow. In order to account for this difference of action, it is necessary to take into consideration, that magnesia has less affinity for carbonic acid, ihan lime has, and that, consequently, when the earths are mingled together, the magnesia preserves its causticity, cven when the lime is saturated with carbonic acid, and brought back to the state of limestone. Thus it appears that magnesia can preserve its caustic properties, and exercise its deleterious effects upon vegetation, curing a long time.

The use of plaster, or gypsum, which has become common in Europe as a manure, is one of the most important improvements

that has ever been made in agriculture. It has even been introduced into America, where it was made known by Franklin upon his return from Paris. As this celebrated philosopher wished that the effects of this manure should strike the gaze of all cultivátors, he wrote in great letters, formed by the use of the ground plaster, in a field of clover lying upon the great road to Washington, “This has been plastered.” The prodigious vegetation which was developed in the plastered portion led him to adopt this method. Tolumes upon excellence of plaster would not have produced so speedy a revolution. From that period the Americans have imported great quantities of plaster of Paris.

There are, however, some tracts of country where the use of plaster has been attempied without success. But this arose from its being one of the original constituents of the soil, which derire no advantage from the addition of a new quantity. The existence of this salt, naturally in those lands upon which plaster produced little or no effect has been proved by analysis.

Gypsum is a compound of sulphuric acid and limc, containing more or less of the water of crystallization. A moderate heai de. prives it of its water of crystallization, and renders it opaque. It can then be reduced to powder and employed in that state. Though ibe prepared gypsum absorbs water with avidity, and its consistency is affected by the mixture, it may be preserved many months without its properties being sensibly affected. Nothing more is necessary for this purpose than to head it up in tight casks.

Gypsum carefully broken is likewise much used, and there are some farmers who attribute to it the same efficacy as is possessed by that prepared by heat. I have myself made some comparative

ced a little more effect the first year, but during the three years which followed, the difference was almost nothing.

The gypsum is scattered by the hand, at the time when the leaves of the plants begin to cover the ground, and it is best to take advantage of a light rain for the operation, as it is thought to be beneficial to have the leaves moistened, in order that they retain a small portion of the powder. · The effect of the gypsum is perceptible during three or four years. The use of it can be resumed at the end of that time. The quantity in which it is usually employed is from 2 cwt. to 3 cwt. per acre.

Much has been said upon the effecis of plaster. Some have pretended that its action might be attributed to the force with which it absorbs water. But it solidifies that liquid and does not part with it either to the atmosphere, or any other surrounding body; so that this doctrine does not appear well founded. Besides, if its action were from this cause, it would be momentary, and would cease after the first rains; and this is contradicted by experience. More. over, it is believed that the broken gypsum has not the property of absorbing water; and yet it produces nearly the same effects as the baked and powdered plaster.

Others have thought that plaster acted only by favoring the putrefactions of animal substances, and the decomposition of manures. But Davy has resuted this opinion by direct experiment, placing it beyond a doubt, that the mixture of plaster with manure, whether animal or vegetable, does not facilitate decomposition.

There are others, again, who attribute the effects of plaster to its stimulating properties; and these adopt, in its utmost extent the opinion which I have formed upon this subject. It still remains, however, to be explained, why this salt which is not more stimulating than many others, acts with so much better effect, and why its action is continued during several years, whilst that of others is exhausted in so much less time, why this salt never dries plants, whilst the others, if employed in excess, burn them up and destroy them. These are problems which remain to be solved, and of which the solution cannot be found in the stimulating properties of the plaster.

Hitherto it has been sufficient to state the good effects of plaster, in order that agriculture might be enriched by so important a discovery. The fact alone is sufhcient for the farmer, and it is not the only one in which the theory can add nothing to the practice. I shall, however, give here a few ideas upon the action of plaster; and I publish them with the more confidence, because they appear to me to be deduced from well established analogies.

It is proved, that those salts which have a base of lime or alkali are the most abundant in plants. Analysis also shows that the different salts do not exist in the same proportion, either in plants of different kinds, or in the different parts of the same plant.

On the other hand, observation shows us every day, that these substances, to be beneficial to plants, must be presented to them in proper proportions; for if too great a quantity of salts easily soluble in water, be mixed with the soil, the plants will wither and die; though they will languish, if totally deprived of the salts. A little marine salt, mixed with dung and spread upon the soil, excites the organs of plants and promotes vegetation; but too much will produce a pernicious effect upon them.

If we now consider that salts can act upon plants, only in proportion to their solubility in water, through which medium they are conveyed. we can conceive, that those which are least valuable will be productive of the greatest advantage.

Water can hold in solution at any one time but a small portion of these saline substances; and as they will always be conveyed into plants in the same proportions, their effect will be equal and constant, and will be continued till the soil be exhausted of the salts. The length of this period will be according to the quantity of them, which is contained in the soil, and to the plants not being rendered liable to receiving more of them than it needs.

The solubility of plaster in water appears to be precisely the de

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