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T. O there are many things in common life that belong to the deepest of sciences. Making tea is the chemical operation called infusion, which is, when a hot liquor is poured upon a substance in order to extract something from it. The water, you see, extracts from the tea-leaves their colour and flavour. P. Would not cold water do the same?

T. It would, but more slowly. Heat assists almost all liquors in their power of extracting the virtues of herbs and other substances. Thus, good housewives formerly used to boil their tea, in order to get all the goodness from it as completely as possible. The greater heat and agitation of boiling makes the water act more powerfully. The liquor in which a substance has been boiled is called a decoction of that substance.

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P. Then we had a decoction of mutton at dinner to-day. T. We had-broth is a decoction, and gruel and barleywater are decoctions.

P. And ink

T. No-the materials of which ink is composed are steeped in a cold liquor, which operation is termed maceration. In all these cases, you see, the whole substance does not mix with the liquor, but only part of it. The reason of which is, that part of it is soluble in the liquor, and part not.

P. What do you mean by soluble?

T. Solution is when a solid put into a fluid entirely disappears in it, leaving the liquor clear. Thus, when I throw this lump of sugar into my tea, you see it gradually wastes away till it is all gone, the tea remaining as clear as before, though I can tell by the taste that the sugar is dispersed through all parts of it. The body which thus disappears, is said to be soluble, and the liquor it dissolves in, is called the solvent, or menstruum. P. Salt is a soluble substance.

T. Yes. But what if I were to throw a lump of chalk into some water?

P. It would make the water white.

T. While you stirred it—no longer; afterwards it would sink undissolved to the bottom.

P. Chalk, then, is not soluble.

T. No, not in water; when stirred up in a liquor so as to cause it to lose its transparency, it is said to be diffused. Now, suppose you had a mixture of sugar, salt, chalk, and tea-leaves, and were to throw it into water, either hot or cold; what would be the effect?

P. The sugar and salt would disappear, being dissolved. The tea-leaves would yield their colour and taste. And the chalk

T. The chalk would sink to the bottom with the tea-leaves, unless the water were stirred, when it would be rendered turbid or muddy. After the operation, the tea-leaves, if dried and weighed, would be found to have lost part of their weight, and the water would have gained it,

P. When I observed that chalk was insoluble, you said pointedly, in water it is: I suppose, then, that in some other liquid it is soluble.

T. Yes-in acids; that is, in vinegar and other liquids of a similar class. Indeed, in proper menstrua, not only is chalk soluble, but most other bodies; even the metals, those solid and seemingly indestructible bodies, by being put into certain liquids, become converted into transparent fluids.

P. How exceedingly curious!

T. It is. Upon this principle are founded many curious matters in the arts. Thus, spirit-varnish is made of a solution of various gums or resins in spirits, that will not dissolve in water. Therefore, when it has been laid over any substance with a brush, and is become dry, the rain or the moisture of the air will not affect it. This is the case with the beautiful varnish laid upon coaches. On the other hand, the varnish left by gum-water could not be washed off by spirits.

P. I remember, when I made gum-water, upon setting the cup in a warm place, the water all dried away, and left the gum just as it was before. Would the same happen if I had sugar or salt dissolved in the water.

T. Yes, upon exposing the solution to warmth, it would dry away, and you would get back your salt or sugar in a solid state, as before.

P. But if I were to do so with a cup of tea, what should I get?

T. Not tea-leaves, certainly! But your question makes a few observations necessary. It is the property of heat to make most things fly off in vapour, which is called evaporation, or exhalation. But this it does in very different degrees to different substances, Some are easily made to evaporate; others with more difficulty, and others not at all by the most violent fire we raise. Fluids in general are easily evaporable; but not equally so. Spirit of wine flies off in vapour much

sooner than water; so that if you had a mixture of the two, by applying a gentle heat you might drive off almost all the spirit, while the greater part of the water would remain. Water, again, is more evaporable than oil. Some solid substances are much disposed to evaporate; thus, smelling-salts by a little heat may entirely be driven away in the air. But, in general, solids are more fixed than fluids; and, therefore, when a solid is dissolved in a fluid, it may commonly be recovered again by evaporation. It is by this operation that common salt is obtained from sea-water and salt-springs, either by the artificial application of heat, or by the natural heat of the sun. When a quantity of water contains as much salt as it will dissolve, it is called a saturated solution; upon evaporating which a little, the salt begins to assume the solid state, forming little regular masses called crystals. Sugar may be made in like manner to form crystals, and then it is sugar-candy. But, now to your question about tea. On exposing it to considerable heat, those fine particles in which its flavour consists, being as volatile or evaporable as the water, would fly off along with it; and when the infusion came to dryness, there would be left only those particles in which its roughness and colour consist. would make what is called an extract of a plant.

This

P. What becomes of the water that evaporates? T. A very proper question-it ascends into the air, and unites with it, causing it to become moist or dewy. But if, however, the vapour in its way happen to be stopped by any cold body, it is condensed—that is, it returns to the state of water again. Lift up the lid of the tea-pot, and you will see water collected on the inside of it, which is the condensed steam which rises from the hot tea beneath it. Hold a spoon or knife in the way of the steam which bursts out from the spout of the tea-kettle, and you will find it immediately covered with drops of water. This operation of turning a liquid into vapour, and then condensing it, is called distillation. For this purpose, the vessel in which the liquor is heated is closely covered with another called the head, into which the steam rises and is condensed. It is then drawn off by means of a pipe from this vessel called a still, into another called a receiver. In this way all sweet-scented and aromatic liquors are drawn from fragrant vegetables by means of water or spirits. The fragrant part being very volatile, rises along with the steam of the water or spirit, and remains united with it after it is condensed. Rosewater and spirit of lavender are liquors of this kind.

P. I think I have heard of making salt water fresh by means of distillation.

T. Yes, that is an old discovery lately revived. The salt in sea-water being of a fixed nature, does not rise with the steam; and, therefore, on condensing the steam, the water is found to be fresh. And this indeed is the method nature employs in raising water by exhalation from the ocean, which, collecting in clouds, is condensed in the cold regions of the air, and falls down in rain.-But our tea is done; so we will now put an end to our chemical lecture.

SECTION VII.

NARRATIVE, DESCRIPTION, ALLEGORY, &c.

STORY OF A DISABLED SOLDIER.

OLIVER GOLDSMITH.

NO OBSERVATION is more common, and, at the same time, more true, than "that one half of the world are ignorant how the other half live." The misfortunes of the great are held up to engage our attention, are enlarged upon in tones of declamation; and the world is called upon to gaze at the noble sufferers. The great, under the pressure of calamity, are conscious of several others sympathizing with their distress; and have, at once, the comfort of admiration and pity.

There is nothing magnanimous in bearing misfortunes with fortitude when the whole world is looking on: men in such circumstances will act bravely even from motives of vanity. But he who, in the vale of obscurity, can brave adversity,who, without friends to encourage, acquaintances to pity, or even without hope to alleviate his misfortunes, can behave with tranquillity and indifference, is truly great: whether peasant or courtier, he deserves admiration, and should be held up for our imitation and respect.

I have been led into these reflections from accidentally meeting, some days ago, a poor fellow, whom I knew when a boy, dressed in a sailor's jacket, and begging at one of the

outlets of the town, with a wooden leg. I knew him to be honest and industrious when in the country, and was curious to learn what had reduced him to his present situation. Wherefore, after giving him what I thought proper, I desired to know the history of his life and misfortunes, and the manner in which he was reduced to his present distress. The disabled soldier,—for such he was, though dressed in a sailor's habit,-scratching his head, and leaning on his crutch, put himself into an attitude to comply with my request, and gave me his history as follows:

"As for my misfortunes, master, I can't pretend to have gone through any more than other folks; for, except the loss of my limb, and my being obliged to beg, I don't know any reason, thank Heaven, that I have to complain. There is Bill Tibbs, of our regiment, he has lost both his legs, and an eye to boot; but, thank Heaven! it is not so bad with me yet.

"I was born in Shropshire. My father was a labourer, and died when I was five years old; so I was put upon the parish. As he had been a wandering sort of a man, the parishioners were not able to tell to what parish I belonged, or where I was born; so they sent me to another parish, and that parish sent me to a third. I thought, in my heart, they kept sending me about so long, that they would not let me be born in any parish at all; but at last, however, they fixed me. I had some disposition to be a scholar, and was resolved, at least, to know my letters; but the master of the work-house put me to business as soon as I was able to handle a mallet: and here I lived an easy kind of a life for five years. I only wrought ten hours in the day, and had my meat and drink provided for my labour. It is true, I was not suffered to stir out of the house, for fear, as they said, I should run away. But what of that? I had the liberty of the whole house, and the yard before the door; and that was enough for me. I was then bound out to a farmer, where I was up both early and late; but I ate and drank well, and liked my business well enough, till he died, when I was obliged to provide for myself; so I was resolved to go and seek my fortune.

"In this manner I went from town to town, worked when I could get employment, and starved when I could get none; when, happening one day to go through a field belonging to a justice of peace, I spied a hare crossing the path just before me; and I believe the Evil One put it in my head to fling my stick at it—well, what will you have on't?-I killed the

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