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fingers of a dead man's hand, and her eyes rested on the blanched cheekbones and whitened skull of a human skeleton! Yes, it was Henry. At a short distance was found a bottle, which had contained laudanum, enclosed in a sheet of paper, written in a wild, incoherent manner, leaving no doubt as to the manner or cause of his

death, under a total deprivation of mental faculty. Amelia awoke once more from a state of lethargic stupefaction to sense and reason. She gave the above brief sketch, clutched her hands, closed her eyes with a shudder, laid her head back upon her pillow, and her pure spirit returned to HIM who gave it.

(Sel. Mag.)

CHEMICAL ESSAYS. NO. I.

INTRODUCTION—HOMOGENEOUS AND HETEROGENEOUS ATTRACTION—CALORIC.

THERE is perhaps no branch of science which has improved so rapidly within the last thirty years as that of Chemistry. Before that time it wanted regular classification, and was entirely veiled from the eyes of all but the professed philosopher, owing to the confusion of its nomenclature. But now it presents to all an interesting field of enquiry, which will amply repay the casual as well as the unintermitting labourer. By the help of this science, he may examine and admire the works of the great Creator of the universe, as well in the objects which are constantly before him, as in the grander operations of nature. To give a brief outline of this interesting branch of knowledge will be the object of this and the following papers.

The investigation of the properties and mutual action of elementary parts of bodies, and all changes in the constitution of matter, whether effected by heat, mixture, or any other means, may be considered as the peculiar province of chemistry. It must therefore be one of the most diffuse subjects upon which we can enter; and to treat it with regularity will be indispensably necessary. Let us first then take a view of the powers and properties of matter connected with chemical changes. These may be viewed under the heads of

1. HOMOGENEOUS ATTRACTION.
II. HETEROGENEOUS ATTRACTION.
III. CALORIC, OR HEAT.
IV. ELECTRICITY.

Homogeneous attraction, or the attrac-
tion of cohesion, always tends to the
union of particles of the same nature.
6 ATHENEUM VOL. 1. new series.

We

This it is which under the name of
gravitation attracts all bodies to the
earth. The chief connexion it has with
chemistry is, that it may be considered
as being the primary cause of crystal-
lization; a subject upon which our
narrow limits and its present uncertain-
ty must prevent our enlarging.
will therefore pass on to heterogeneous
or chemical attraction. This from
some property unknown to man, causes
particles of different natures to unite in
various manners. If into a glass con-
taining a piece of copper, some nitric
acid be poured, the acid will immedi-
ately unite with the copper, and form a
new compound, which does not partake
of the properties of its elements, but
presents a distinct character. This is
the first thing we should observe in the
unions caused by chemical attraction;
that, for the most part, the compound
formed differs entirely from both its el-
ements; whereas, in the unions caused
by homogeneous attraction, no change
in the nature of the matter acted upon
can take place. Thus, in the case be-
fore us the acidity of the nitric acid is
gone, and a body remains which par-
takes of none of its powers. The
chemical nature of the body is not the
only thing that experiences a change.
Frequently the colour and solidity of
the body are equally affected.
In the
case before us, the resulting compound
is of a beautiful blue colour, which was

* Nitric acid will be treated of in the course of

these papers. For the sake of preserving regularity

no more than its name can now be mentioned.

It

may be obtained at the chemist's, by any persons desirous of trying the experiment, but great care should be taken in using it, as it is a very corrosive

fluid, and rapidly destro s clothes.

seen in neither of the original bodies. matters. A single column of this sort Solids are changed by it into aëriform is here introduced as a specimen. shapes, as when gunpowder is inflamed.

But we may also observe that, during the process of this union, great commotion appears in the bodies acted upon. This is the case in the instance to which we have already alluded. A great deal of air is extricated during the decomposition of the copper. In many unions, however, the immediate effect is much greater. If sulphuric acid* be added to water, in the proportion of four pounds of the latter, so much heat will be produced in the mixture as to raise the thermometer to 300° Farenheit.

We shall also find that, after a time, this commotion will cease: from which we may learn that nitric acid and copper will only unite in certain propor

tions.

Another very important fact in the system of chemical attraction is, that different bodies are possessed of different attractive powers. If into the solution (chemically termed nitrate of copper) which we obtained in the former experiment, a piece of iron be immersed, you will perceive that it will be immediately covered with a thin coating of copper. The cause of this is, that the nitric acid has a greater affinity to the iron, than to the copper it holds in solution; that, consequently, it quits the copper and forms a new compound with the iron; the copper being thus relinquished is precipitated, and forms that thin coating which you may observe on the surface of the iron. Upon this principle depends the power of chemically decomposing bodies, i. e. reducing them to their original matters. Here the copper is first dissolved by the acid, and then the compound thus formed is decomposed by the intervention of the iron, and the copper restored in its former state. On this principle it is that chemical tables have been formed, by which at one view the chemist may be informed of the various powers of attraction between different

Further mention of sulphuric acid must be postponed for the same reason as that of nitric. It may be obtained at the chemist's. Greater care should be taken of this than the nitric, as it destroys not only clothes, &c. but also animal fibre, and consequently would cause'painful wounds.

SULPHURIC ACID.

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From this table we should deduce that sulphuric acid had a greater affinity to baryta than to strontia, to strontia than to potassa, to potassa than to soda, and so on; and, consequently, that baryta would decompose any compound of sulphuric acid formed with those bases enumerated after it. There are two classes of decomposition, simple and double. In the simple, one body separates a second from its combination with a third. In the double, two new compounds are formed; as when nitrate of baryta* and sulphate of soda are mixed, the nitric acid of the former compound quits its form, and enters into a new compound with the soda; while the sulphuric acid quits the soda, and enters into a new compound with the baryta: so that two new compounds, nitrate of soda and sulphate of baryta, are formed. It is evident from what has been said, that there are some laws which govern the union of particles of different natures. Concerning these and concerning the causes propelling the particles to unite, many conjectures have been made, but nothing certain has been discovered. Some suppose

that all particles of matter are endued with one of the two electricities, and that these subtle fluids are always tending to unite. But as we do not intend to enter upon the more abstruse points of chemistry, but merely to take a general and popular view of the science, we will pass on to the next general power alluded to, heat or caloric.

It is

There are many doubts entertained as to the nature of this agent. however generally supposed to be a fluid pervading, more or less, all matter, and has been divided into

I. FREE CALORIC. II. SPECIFIC HEAT, or COMBINED CALORIC.

Although the reader may not yet know what these drugs are, he may still make the experiments alluded to. It would be quite impossible to preserve any regularity of design, if we stopped to explain the nature of each drug alluded to by way of example. They will all of them be explained hereafter.

The name caloric has been proposed in the new nomenclature as a substitute for heat, which has by common use been applied merely to the sensation of heat. One of the great characteristics of caloric is, that it always tends to an equilibrium. It may be supposed that there are rays of caloric flowing in all conceivable directions from all bodies. But when any body is below the temperature of those around it, the rays of caloric flowing from it are not equal in number to those which it has a capacity for receiving, and consequently its temperature is gradually heated to the same warmth with the objects around it. When bodies are once raised to the same temperature with the atmosphere around them, they radiate and absorb caloric in equal quantities, so that they preserve their equilibrium. Cold is merely a negative subject, implying the absence of heat. Thus, when we lay our hand upon a marble slab, the feeling of cold which we experience, is merely the caloric flowing from our hand into the marble, and endeavouring to raise the marble to the same temperature.

We have already observed that caloric is proceeding in different rays from all bodies. This is called the radiation of caloric. Different bodies have different radiating powers. This has been clearly proved by the experiments of Mr. Leslie. All heat which is perceptible to the senses may be considered as free caloric..

Besides the power of radiation, caloric may be reflected, subject to the same laws as those which govern optical reflection.-Another very important power of caloric is, its expanding all bodies, and thus acting in direct opposition to the attraction of cohesion. It effects this by introducing its particles between the particles of the body upon which it acts. The power of bodies to bear in this way the introduction of caloric between their particles, is called their conducting power. All bodies have more or less the power of conducting caloric, but some possess it in a much stronger degree than others. Generally the denser bodies, such as metals, &c. are the best conductors of caloric. Porous substances, such as wood, cork, &c.

are the worse conductors, down to woollen cloth, flannel, and down, which is one of the lightest bodies and at the same time one of the worst conductors. The reason of this may probably be, that in the dense substances there is much less air, which scarcely conducts caloric at all. On this principle of the different conducting powers of bodies, depends the mode of clothing ourselves. Flannel and woollen dresses being very bad conductors of caloric, prevent, when the temperature of the atmosphere is lower than that of our bodies, the escape of the animal heat from them, and thus keep us warm in the winter season. The same dress would keep us cool when the atmosphere was warmer than our body, as it would prevent its penetrating to our frame. If you lay your hand on a piece of marble, on the wood of the table, and on the carpet of the room, they will all appear to you to be of different temperatures; the marble coldest, the wood medium, the carpet warmest, and yet the thermometer would inform you that they are really of the same temperature. The reason of this is, that the marble being the best conductor of caloric of the three, (as they are all of a temperature below that of your hand, though of the same with the atmosphere,) absorbs from you the caloric you possess more rapidly than the others; and though it really makes you no colder than the others would in the end, yet as it produces the same effect in a shorter time, the change is more sudden, and consequently the sensation of cold (which we must always remember is merely the abstraction of caloric) is much greater. The reverse of this would be seen, from the same cause, were we to put three pieces of ice on the various bodies enumerated. In this case, that on the marble would first be melted, that on the wood next, and that on the carpet last, because, here the conducting power would act the other way, and induce the marble to part with its excess of caloric to the ice more readily than the wood or the carpet could do. And here we must admire and adore the gracious dispensations of a Being who has stooped to adapt the various

coverings of his creatures to the circumstances in which they are placed. Who has provided those most exposed to cold with furs or with plumage, and who has especially guarded with down (the

worst conductor of caloric known to us) the breast of aquatic birds, which is the part most exposed to the action of the water.

ORIGINAL LETTERS.

(Lit. Gaz.)

PRIVATE CORRESPONDENCE OF WILLIAM COWPER, ESQ.
WITH SEVERAL OF HIS MOST INITIMATE FRIENDS.

THE mingled character of Cowper is finely displayed in these Letters, and they are full of anecdote and remark upon the literature of the preceding generation. From grave to gay the transitions are charming; but we will offer no farther comment on volumes which we can illustrate in so gratifying a way by the following almost unselected extracts:

"To JOSEPH HILL, Esq.

"Jan. 21, 1769.

"DEAR JOE,--I rejoice with you in your recovery, and that you have escaped from the hands of one from whose hands you will not always escape. Death is either the most formidable, or the most comfortable thing, we have in prospect, on this side of eternity. To be brought near to him, and to discern neither of these features in his

face, would argue a degree of insensibility, of which I will not suspect my friend, whom I know to be a thinking man. You have been brought down to the sides of the grave, and you have been raised again by Him who has the keys of the invisible world; who opens, and none can shut, who shuts, and none can open. I do not forget to return thanks to Him on your behalf, and to pray that your life, which He

even within the same paragraph, of the adventitious, or perhaps we should say, the habitual, and the natural. The change from one to the other, at the last clause, is striking.

favour of your last, and ready enough to "Though much obliged to you for the acknowledge the debt, the present, however, is not a day in which I should have chosen to pay it. A dejection of mind, which perhaps may be removed by to-morrow, rather disqualifies me for writing,-a business 1 would always perform in good spirits, bewhere there is much sympathy to assist the cause melancholy is catching, especially contagion. But certain poultry, which I understand are about to pay their respects companion, and I find myself obliged to to you, have advertised for an agreeable embrace the opportunity of going to town with them in that capacity."

to remember upon this occasion) that Sam - - - " I remember (the last thing I mean Cox, the counsel, walking by the sea-side, as if absorbed in deep contemplation, was questioned about what he was musing on. He replied, I was wondering that such an almost infinite and unwieldy element should produce a sprat!'

The following is very pleasant and

has spared, may be devoted to his service, natural, and the style of it is the per

'Behold! I stand at the door and knock,' is the word of Him, on whom both our mortal and immortal life depend, and blessed be his name; it is the word of one who wounds only that He may heal, and who waits to be gracious. The language of every such dispensation is, 'Prepare to meet thy God.' It speaks with the voice of mercy and goodness, for without such notices, whatever preparation we might make for other events, we should make none for this. My dear friend, I desire and pray, that when this last enemy shall come to execute an unlimited commission upon ns, we may be found ready, being established and rooted in a well-grounded faith in His name, who conquered and triumphed over him upon his Cross.

Yours ever,

W. C.

We extract the following short pas sage for the purpose of pointing out the singular mixture which it presents,

fection of easy simplicity. The occasion was that of having just converted a little summer-house in his garden into a writing-room.

"It is an observation that naturally occurs upon the occasion, and which many other occasions furnish an opportunity to make, that people long for what they have not, and overlook the good in their possession. This is so true in the present instance, that for years past I should have thought myself happy to enjoy a retireinent even less flattering to my natural taste than this in which I am now writing; and have often looked wistfully at a snug cottage, which, on account of its situation at a distance from noise and disagreeable objects, seemed to promise me all I could said to be local; never once adverting to wish or expect, so far as happiness may be this comfortable nook, which affords me all that could be found in the most sequestered

bermitage, with the advantage of having all those accommodations near at hand which no bermitage could possibly afford me. People imagine they should be happy in circumstances which they would find in supportably burthensome in less than a week. A man that has been clothed in fine linen, and fared sumptuously every day, envies the peasant under a thatched hovel; who, in return, envies him as much his palace and his pleasure-ground. Could they change situations, the fine gentleman would find his ceilings were too low, and that his casements admitted too much wind; that he had no cellar for his wine, and no wine to put in his cellar. These, with a thousand other mortifying deficiencies, would shatter his romantic project into innumerable fragments in a moment. The clown, at the same time, would find the accession of so much unwieldy treasure an incumbrance quite incompatible with an hour's ease. His choice would be puzzled by variety. He would drink to excess, because he would foresee no end to his abundance; and he would eat himself sick for the same reason. He would have no idea of any other happiness than sensual gratification; would make himself a beast, and die of his good fortune. The rich gentleman had, perhaps, or might have had, if he pleased, at the shortest notice, just such a recess as this; but if he had it, he overlooked it, or, if he had it not, forgot that he might command it whenever he would. The rustic, too, was actually in possession of some blessings, which he was a fool to relinquish, but which he could neither see nor feel, be cause he had the daily and constant use of them; such as good health, bodily strength, a head and a heart that never ached, and temperance, to the practice of which he was bound by necessity, that, humanely speak ing, was a pledge and a security for the continuance of them all.

"Thus I have sent you a school-boy's theme."

The following is another singular compound of gloom and humour. It would be worth extracting, if it were only for the capital simile about the ri

ot-act.

"I do not at all doubt the truth of what you say, when you complain of that crowd of trifling thoughts that pesters you without ceasing; but then you always have a serious thought standing at the door of your imagination, like a justice of peace, with the riot-act io bis hand, ready to read it, and disperse the mob. Here lies the difference between you and me. My thoughts are clad in a sober livery, for the most part as grave as that of a bishop's servants. They turn too upon spiritual subjects, but the tallest fellow and the loudest amongst them all, is he who is continually crying with a loud voice, Actum est de le, periisti. You wish for more attention, I for less. Dis sipation itself would be welcome to me, so

it were not a vicious one; but however earnestly invited, it is coy, and keeps at a distance. Yet with all this distressing gloom upon my mind, I experience, as you do, the slipperiness of the present hour, and the rapidity with which time escapes me. Every thing around us, and every thing that befalls us, constitutes a variety, which, whether agreeable or otherwise, has still a thievish propensity, and steals from us days, months, and years, with such unparalleled address, that even while we say they are here, they are gone. From infancy to manhood is rather a tedious period, chiefly, I suppose, because at that time we act under the control of others, and are not suf fered to have a will of our own. But thence downward into the vale of years, is such a declivity, that we have just an opportunity to reflect up a the steepness of it, and then find ourselves at the bottom."

The passage which follows we should willingly have passed over, if we could have persuaded ourselves that it really belonged to Cowper. We can only trust ourselves to say that it is addressed to the Rev. Mr. Newton, the poet's friend and religious Mentor-a person who not long afterwards "improved the occasion" of Handel's celebrated Commemoration,by preaching a sermon on the profanation of that ceremony!

"He seems, together with others of our acquaintance, to have suffered considerably in his spiritual character by his attachment to music. The lawfulness of it, when used with moderation, and in its proper place, is unquestionable; but I believe that wine itintoxication, does not more debauch and self, though a man be guilty of habitual befool the natural understanding, than music, always music, music in season and out of season, weakens and destroys the spiritual discernment. If it is not used with an unfeigned reference to the worship of God, and with a design to assist the soul in the performance of it, which cannot be the case when it is the only occupation, it

degenerates into a sensual delight, and becomes a most powerful advocate for the admission of other pleasures, grosser perhaps in degree, but in their kind the same."

We meet with several passages in these volumes in which Cowper roundly asserts that all the light and humourous passages in his poetry are mere tricks-invented purely to inveigle the reader into listening to something more serious and useful. To this, as before, we shall only venture to say, that the passages in question occur in letters adHere are dressed to Mr. Newton. two of them:

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