Imágenes de páginas

She gave

fingers of a dead man's hand, and her death, under a total deprivation of meneyes rested on the blanched cheek- tal faculty. * * Amelia awoke once bones and whitened skull of a human more from a state of lethargic stupeskeleton ! Yes, it was Henry. At a faction to sense and reason. short distance was found a bottle, the above brief sketch, clutched her which had contained laudanum, enclos- hands, closed her eyes with a shudder, ed in a sheet of paper, written in a laid her head back upon her pillow, wild, incoherent manner, leaving no and her pure spirit returned to Him doubt as to the manner or cause of his who gave it.


ISTRODUCTION-HOMOGENEOUS AND HETEROGENEOUS ATTRACTION-CALORIC. THERE is perhaps no branch of This it is which under the name of

science which has improved so gravitation attracts all bodies to the rapidly within the last thirty years as earth. The chief connexion it has with that of Chemistry. Before that time it chemistry is, that it may be considered wanted regular classification, and was as being the primary cause of crystalentirely veiled from the eyes of all but lization ; a subject upon which our the professed philosopher, owing to the narrow limits and its present uncertainconfusion of its nomenclature. But ty must prevent our enlarging. We now it presents to all an interesting field will therefore pass on to heterogeneous of enquiry, which will amply repay the or chemical attraction. This from casual as well as the unintermitting la- some property unknown to man, causes bourer. By the help of this science, particles of different natures to unite in he may examine and admire the works various manners. If into a glass conof the great Creator of the universe, as taining a piece of copper, some nitric well in the objects which are constantly acid * be poured, the acid will immedibefore him, as in the grander operations ately unite with the copper, and form a of nature. To give a brief outline of new compound, which does not partake this interesting branch of knowledge of the properties of its elements, but will be the object of this and the follow- presents a distinct character. This is ing papers.

the first thing we should observe in the The investigation of the properties unions caused by chemical attraction ; and mutual action of elementary parts that, for the most part, the compound of bodies, and all changes in the con- formed differs entirely from both its elstitution of matter, whether effected by ements ; whereas, in the unions caused heat, mixture, or any other means, may by homogeneous attraction, no change be considered as the peculiar province in the nature of the matter acted upon or chemistry. It must therefore be one cah take place. Thus, in the case beof the most diffuse subjects upon which fore us the acidity of the nitric acid is we can enter; and to treat it with reg- gone, and a body remains which parularity will be indispensably necessary. takes of none of its powers. The Let us first then take a view of the chemical nature of the body is not the powers and properties of matter con- only thing that experiences a change. nected with chemical changes. These Frequently the colour and solidity of may be viewed under the heads of the body are equally affected. In the 1. HOYOGENEOUS ATTRACTION.

case before us, the resulting compound UI. HETEROGENEOUS ATTRACTION, is of a beautiful blue colour, which was III. CALOBIC, On Hear.

IV. ELECTRICITI. Homogeneous attraction, or the attrac- these paperen For the sake of preserving regularity tion of cohesion, always tends to the may be obtained at the chemist's, by any persons union of particles of the same nature. should be taken in using it, as it is a very corrosive 6 ATHENEUM VOL. 1. new scries.

fluid, and rapidly destrn s clothes.

* Nitric acid will be treated of in the course of

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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.

SULPHURIC ACID. 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 From this table we should deduce great deal of air is extricated during that sulphuric acid had a greater affinity the decomposition of the copper. In to baryta than to strontia, to strontia many unions, however, the immediate than to potassa, to potassa than to soda, effect is much greater. If sulphuric ac- and so on; and, consequently, that baid* be added to water, in the proportion ryta would decompose any compound of four pounds of the latter, so much of sulphuric acid formed with those baheat will be produced in the mixture as ses enumerated after it. to raise the thermometer to 300° Far- two classes of decomposition, simple enheit.

and double. In the simple, one body We shsll also find that, after a time, separates a second from its combinathis commotion will cease : from which tion with a third. In the double, two we may learn that nitric acid and cop- new compounds are formed ; as when per will only unite in certain propor- nitrate of baryta* and sulphate of soda tions.

are mixed, the nitric acid of the former Another very important fact in the compound quits its form, and enters system of chemical attraction is, that into a new compound with the soda ; different bodies are possessed of differ- while the sulphuric acid quits the soda, ent attractive powers. If into the so- and enters into a new compound with lution (chemically termed nitrate of the baryta : so that two new comcopper) which we obtained in the for- pounds, nitrate of soda and sulphate of mer experiment, a piece of iron be im baryta, are formed. It is evident from mersed, you will perceive that it will be what has been said, that there are some immediately covered with a thin coat- laws which govern the union of particles ing of copper. The cause of this is, of different natures. Concerning these that the nitric acid has a greater affinity and concerning the causes propelling to the iron, than to the copper it holds the particles to unite, many conjectures in solution; that, consequently, it quits have been made, but nothing certain the copper and forms a new compound has been discovered. with the iron; the copper being thus that all particles of matter are endued relinquished is precipitated, and forms with one of the two electricities, and that thin coating which you may ob- that these subtle fluids are always tendserve on the surface of the iron. Upon ing to unite. But as we do not intend this principle depends the power of to enter upon the more abstruse points chemically decomposing bodies, i.e. re- of chemistry, but merely to take a genducing them to their original matters. eral and popular view of the science, Here the copper is first dissolved by we will pass on to the next general the acid, and then the compound thus power alluded to, heat or caloric. formed is decomposed by the interven There are many doubts entertained tion of the iron, and the copper restored as to the nature of this agent. It is in its former state. On this principle however generally supposed to be a it is that chemical tables have been fluid pervading, more or less, all matformed, by which at one view the ter, and has been divided into chemist may be informed of the various I. FREE CALORIC. powers of attraction between different II. Speciric Heat, or COMBINED CALORIC.

Some suppose

* Further mention of sulphuric acid must be postponed for the same reason as that of vitric. 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.

* 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 bereafter.

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The name calorie has been proposed are the worse conductors, down to woolin the new nomenclature as a substi- len cloth, flannel, and down, which is tute for heat, which has by common use one of the lightest bodies and at the been applied merely to the sensation of same time one of the worst conductors. heat. One of the great characteristics The reason of this may probably be, of caloric is, that it always tends to an that in the dense substances there is equilibrium. It may be supposed that much less air, which scarcely conducts there are rays of caloric flowing in all caloric at all. On this principle of the conceivable directions from all bodies. different conducting powers of bodies, But when any body is below the tem- depends the mode of clothing ourselves. perature of those around it, the rays of Flannel and woollen dresses being very caloric flowing from it are not equal in bad conductors of caloric, prevent, number to those which it has a capacity when the temperature of the atmosfor receiving, and consequently its tem- phere is lower than that of our bodies, perature is gradually heated to the same the escape of the animal heat from warmth with the objects around it. them, and thus keep us warm in the When bodies are once raised to the winter season. The same dress would same temperature with the atmosphere keep us cool when the atmosphere was around them, they radiate and absorb warmer than our body, as it would calorie in equal quantities, so that they prevent its penetrating to our frame. If preserve their equilibrium. Cold is merely you lay your hand on a piece of marble, a negative subject, implying the absence on the wood of the table, and on the of heat. Thus, when we lay our hand carpet of the room, they will all appear upon a marble slab, the feeling of cold to you to be of different temperatures ; which we experience, is merely the cal- the marble coldest, the wood medium, oric flowing from our hand into the the carpet warmest, and yet the thermarble, and endeavouring to raise the mometer would inform you that they marble to the same temperature. are really of the same temperature.

We have already observed that calo- The reason of this is, that the marble ric is proceeding in different rays from being the best conductor of caloric of all bodies. This is called the radia- the three, (as they are all of a temperation of caloric. Different bodies have ture below that of your hand, though of different radiating powers. This has the same with the atmosphere,) absorbs been clearly proved by the experiments from you the caloric you possess more of Mr. Leslie. All heat which is per- rapidly than the others; and though it ceptible to the senses may be consider- really makes you no colder than the ed as free caloric.

others would in the end, yet as it proBesides the power of radiation, calor- duces the same effect in a shorter time, ic may be reflected, subject to the same the change is more sudden, and conselaws as those which govern optical re- quently the sensation of cold (which flection. Another very important pow. we must always remember is merely er of caloric is, its expanding all bodies, the abstraction of caloric) is much and thus acting in direct opposition to greater. The reverse of this would the attraction of cohesion. It effects be seen, from the same cause, were we this by introducing its particles between to put three pieces of ice on the various the particles of the body upon which it bodies enumerated. In this case, that acts. The power of bodies to bear in on the marble would first be melted, this way the introduction of caloric be that on the wood next, and that on the tween their particles, is called their con- carpet last, because, here the conduct. ducting power. All bodies have more ing power would act the other way, and or less the power of conducting caloric, induce the marble to part with its exbut some possess it in a much stronger cess of caloric to the ice more readily degree than others. Generally the than the wood or the carpet could do. denser bodies, such as metals, &c. are And here we must admire and adore the best conductors of caloric. Porous the gracious dispensations of a Being substances, such as wood, cork, &c. who has stooped to adapt the various

coverings of his creatures to the circum- worst conductor of caloric known to
stances in which they are placed. Who us) the breast of aquatic birds, which
has provided those most exposed to cold is the part most exposed to the action
with furs or with plumage, and who of the water.
has especially guarded with down the

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(Lit. Gaz.)

THE mingled character of Cowper even within the same paragraph, of the

is finely displayed in these Let- adventitious, or perhaps we should say,
ters, and they are full of anecdote and the habitual, and the natural. The
remark upon the literature of the pre- change from one to the other, at the
ceding generation. From grave to last clause, is striking.
gay the transitions are charming ; but

“ Though much obliged to you for the we will offer no farther comment on

favour of your last, and ready enougb to volumes which we can illustrate in so acknowledge the debt, the present, however, gratifying a way by the following al- is not a day in which I should have chosen most unselected extracts :

to pay it. A dejection of mind, wbich per.

haps may be removed by to-morrow, rather * To JOSEPH HILL, Esq. disqualifies we for writing,-a business I

would always perform in good spirits, be. « Jan. 21, 1769.

cause melancholy is catching, especially " DEAR JOE,--1 rejoice with you in your where there is mich sympathy to assist the recovery, and that you have escaped from

contagion. the hands of one from whose bands you understand are about to pay their respects

But certain poultry, wbich I will not always escape. Death is either the

to you, have advertised for an agreeable most formidable, or the most comfortable companion, and I find myself obliged to thing, we have in prospect, on this side of embrace the opportunity of going to town eternity. To be brought near to him, and with them in that capacity.” to discern neither of these features in his face, would argue a degree of insensibility, to remember npon this occasion) that Sam

..." I remember (the last thing I mean of which I will not suspect my friend, whom Cox, the counsel, walking by the sea-side, I know to be a thinking man. been brought down to the sides of the

as if absorbed in deep contemplation, was grave, and you have been raised again by questioned about what he was musing on. Him who has the keys of the invisible He replied, 'I was wondering that such an world; who opens, and none can shut,

almost infinite and unwieldy element should who shuts, and none can open. I do not

produce a spral!' forget to return thanks to Him on your be. The following is very pleasant and half

, and to pray that your life, which He natural, and the style of it is the perhas spared, may be devoted to his service,

Behold! I stand at the door and knock,' fection of easy simplicity. The occa-
is tbe word of Him, op wbom both onr mor sion was that of having just converted
tal and immortal life depend, and blessed
be his name; it is the word of one who to a writing-room.

a little summer-house in his garden in-
wounds only that He may heal, and who
waits to be gracious. The language of " It is an observation that naturally oc.
every such dispensation is, 'Prepare to curs upon the occasion, and which many
meet thy God.' It speaks with the voice other occasions furnish an opportunity to
of mercy and goodness, for without such make, that people long for what they have
notices, whatever preparation we might not, and overlook the good in their posses-
make for other events, we should make sion. This is so true in the present in.
none for this. My dear friend, 1 desire and stance, that for years past I should have
pray, that when this last enemy shall come thought myself happy to enjoy a retire-
to execute an unlimited commission upon inept even less flattering to my natural
nis, we may be found ready, being estab taste than this in which I am now writing ;
Jished and rooted in a well-grounded faith and have often looked wistfully at a snug
in His name, who conquered and triumph- cottage, which, on account of its situation
ed over him upon his Cross.

at à distance from noise and disagreeable

W. C. objects, seemed to promise me all I could We extract the following short pas- said to be local; never once adverting to

wish or expect, so far as happiness may be sage for the purpose of pointing out the this comfortable nook, which affords me all singular mixture which it presents, that could be found in the most sequestered

Yours ever,

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bermitage, with the advantage of having it were not a vicious one; but however carall those accommodations near at hand

nestly invited, it is coy, and keeps at a diswhich no beritage could possibly afford

tance. Yet with all this distressing gloom me. People imagine they should be happy

upon my mind, I experience, as you do, in circumstances which they would find in

the slipperiness of the present hour, and supportably borthensome in less than a

the rapidity with which time escapes me. week. A inan that has been clotbed in fine

Every thing around us, and every thing linen, and fared sumptuously every day, that befalls us, constitutes a variety, which, envies the peasant under a thatched hovel; whether agreeable or otherwise, has stili who, in retura, envies him as much his pals a thievisb propensity, and steals' from us ace and bis pleasure-ground. Could they days, months, and years, with such unparchange situations, the fine gentleman would alleled address, thai even while we say they find his ceilings were too low, and that his are here, they are gone. From infancy to casements admitted too much wind; that manhood is rather a tedious period, chiefly, he had no cellar for his wine, and no wine I suppose, because at that time we act unto put in his cellar. These, with a thou. der the control of others, and are not sufsand other mortifying deficiencies, would fered to have a will of our own. But shatter his romantic project into innumera. thence downward into the vale of years, is ble fragments in a moment. The clown, at such a declivity, that we have just an opthe same time, would find the accession of portunity to reflect up a the steepness of it, so much unwieldy treasure an incumbrance and then find ourselves at the bottom." quite incompatible with an hour's ease. His choice would be pozzled by variety.

The passage which follows we should He would drivk to excess, because he willingly have passed over, if we could would foresee no end to his abundance; have persuaded ourselves that it really and he woold eat himself sick for the same belonged to Cowper. We can only reason. He would have no idea of any oth trust ourselves to say that it is addresser happiness than sensual gratification ; would make himself a beast, and die of his ed to the Rev. Mr. Newton, the poet's good fortape. The rich gentleman had, friend and religious Mentor—a person perhaps, er might have had, if he pleased, who not long afterwards “improved at the shortest notice, just such a recess as the occasion of Handel's celebrated this; but if he bad it, he overlooked it, or, if he had it not, forgot that he might com.

Commemoration,by preaching a sermon mand it whenever he would. The rustic, on the profanation of that ceremony ! too, was actually in possession of some

“He seems, together with others of our blessings, which he was a fool to relinquish, acquaintance, to have suffered considerably but which be could neither see nor feel, be in his spiritual character by his attachment cause he had the daily and constant use of

to music. The lawfulness of it, when used them; such as good health, bodily strength; with moderation, and in its proper place, is a bead and a heart that never ached, and unquestionable ; but I believe that wine it

. temperance, to the practice of which he was

self, though a man be guilty of habitual bound by necessity, that, humanely speak. intoxication, does not more debauch and ing, was a pledge and a security for the hefool the natural understanding, than mucontinuance of them all.

sic, always music, inusic in season and out “Thas I have sent you a school-boy's of season, weakens and destroys the spiritheme." .

tual discernment. If it is not used with The following is another singular an unfeigned reference to the worship compound of gloom and buniour. It God, and with a design to assist the soul would be worth extracting, if it were

in the performance of it, which cannot be

the case when it is the only occupation, it only for the capital simile about the ri- degenerates into a sensual delight, and be. ot-act.

comes a most powerful advocate for the *I do not at all doubt the trath of what admission of other pleasures, grosser peryou say, when you complain of that crowd haps in degree, but in their kind the of trifling thoughts that pesters you without same." ceasing ; but then you always have a seri We meet with several passages in ous thought standing at the door of your imagination, like a justice of peace, with the these volumes in which Cowper roundriot-act in bis haod, ready to read it, and ly asserts that all the light and humourdisperse the inob. Here lies the difference

ous passages in his poetry are mere between you and me. My thoughts are tricks invented purely to inveigle the clad in a sober livery, for the most part as grave as that of a bishop's servants. They reader into listening to something more tarp too upon spiritual sabjects, but the serious and useful. To this, as before, tallest fellow and the loudest amongst we shall only venture to say, that the them all, is he who is continually crying passages in question occur in letters ad

Here are Poo wish for more attention, I for less. Dis dressed to Mr. Newton. sipation itself would be welcome to me, so

two of them :

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