T. It would; but such bell-hanging would come rather too dear. Another valuable quality of gold is its fine colour. It will keep its colour fresh for a great many years in a pure and

clear air.

G. But is not gold soft? I have seen pieces of gold bent double.

T. Yes; it is next in softness to lead, and therefore when it is made into coin, or used for any common purposes, it is mixed with a small proportion of some other metal, in order to harden it. This compound metal is called an alloy. Our gold coin has one-twelfth part of alloy, which is a mixture of silver and copper.

G. How beautiful new gold coin is!

T. Yes scarce any metal takes a stamp or impression better; and it is capable of a very fine polish.

G. What countries yield the most gold?

T. South America, the East Indies, and the coast of Africa. Europe affords but little; yet a moderate quantity is got every year from Hungary. Great quantities are now obtained in California in America, and more especially in Australia.

H. But what a fine thing it would be to find a gold mine on one's estate!

T. Perhaps not so fine as you imagine, for many a one does not pay the cost of working. A coal pit would probably be a better thing.

G. For my part, I will be content with a silver mine.
H. But we have none of those in England, I suppose.

T. We have no silver mines properly so called, but silver is procured in some of our lead mines. There are, however, pretty rich silver mines in various parts of Europe; but the richest of all are at Potosi, in Peru, in South America. Shall I now tell you some of the properties of silver?

G. Yes; if you please.

T. It is one of the perfect metals. It is also as little liable to rust as gold, though indeed it readily gets tarnished. G. Does silver melt easily?

T. Silver and gold both melt with more difficulty than lead; not till they are above a common red-heat. As to the weight of silver, it is nearly one-half less than that of gold, being only eleven times the weight of water.

H. Is quicksilver a kind of silver?

T. It takes its name from silver, being very like it in colour; but in reality it is a very different thing, and one of the most singular of the metal kind.

G. It is not malleable, I am sure.

T. Not when it is quick or fluid, as it always is in our climate. But a very great degree of cold makes it solid, and then it is malleable, like other metals.

G. What a weight quicksilver is! I remember taking up a bottle full of it, and I had like to have dropt it again, it was so much heavier than I expected.

T. Yes, it is one of the heaviest of the metals-about fifteen times heavier than water.

H. Is mercury of much use.

T. Yes for a variety of purposes in the arts, which I cannot now very well explain to you. But you will perhaps be surprised to hear that one of the finest red paints is made from quicksilver.

G. A red paint!-which is that?

T. Vermilion or cinnabar, which is a particular combination of sulphur with quicksilver.

H. Is quicksilver found in this country?

T. No. The greatest quantity comes from Spain, Istria, (a peninsula in N. of Adriatic Sea), and South America. It is a considerable object of commerce, and bears a high value, though much inferior to silver. Well-so much for metals at present. We will talk of the rest on some future opportunity.

ON THE DISCOVERIES OF SCIENTIFIC CHEMISTRY.

(SIR HUMPHREy Davy). phenomena of nature, the causes of rain, snow, hail, dew, wind, and earthquakes. It has been called in to the aid of the culinary arts; and its importance in agriculture, in medicine, and the arts of dyeing, bleaching, tanning, and glass-making, is universally acknowledged. Cal-ca're-ous, adj. (L. calx), partaking of the nature of chalk or lime. Ce-rule-um, n. (L.), sky-colour; blue.

Chem'is-try, kim'is-try, n. (Arabic, kimia, the secret art), the science that investigates the nature and properties of the elements of matter, and their mutual actions and combinations-which ascertains the proportions in which these elements unite, and the modes of separating them when united, and which inquires into the laws that preside over all changes in the constitution of matter, whether effected by heat, light, or electricity. As a science, it is connected with all the | Alchy-my, n. (Arabic, kimia), a

visionary science, much cultivated in the sixteenth and seventeenth centuries, which professed to discover the art of transmuting all metals into gold-of producing a universal medicine, or panacea - and other things

equally ridiculous. The labours of the alchymist, although absurd as to their objects, were yet the means of gradually forming a collection of facts, that led ultimately to the establishment of scientific chemistry.

I WILL readily allow, that accident has had much to do with the origin of the arts, as with the progress of the sciences. But it has been by scientific processes and experiments that these accidental results have been rendered really applicable to the purposes of common life. Besides, it requires a certain degree of knowledge and scientific combination to understand and seize upon the facts which have originated in accident. It is certain, that in all fires alkaline substances and sand are fused together and clay hardened; yet for ages after the discovery of fire, glass and porcelain were unknown, till some men of genius profited by scientific combination often observed but never applied. It suits the indolence of those minds which never attempt anything, and which probably, if they did attempt anything, would not succeed, to refer to accident that which belongs to genius. In the progress of an art, from its rudest to its most perfect state, the whole process depends upon experiments. Science is, in fact, nothing more than the refinement of common sense making use of facts already known to acquire new facts. Clays, which are yellow, are known to burn red; calcareous earth renders flint fusible the persons who have improved earthenware made their selections accordingly. Iron was discovered at least one thousand years before it was rendered malleable; and from what Herodotus says of this discovery, there can be little doubt that it was developed by a scientific worker in metals. Vitruvius tells us, that the ceruleum, a colour made of copper, which exists in perfection in all the old paintings of the Greeks and Romans, and on the mummies of the Egyptians, was discovered by an Egyptian king; there is, therefore, every reason to believe that it was not the result of accidental combination, but of experiments made for producing or improving colours. Amongst the ancient philosophers many discoveries were attributed to Democritus and Anaxagoras; and, connected with chemical arts, the narrative of the inventions of Archimedes alone, by Plutarch, would seem to show how great is the effect of science in

creating power. In modern times the refining of sugar, the preparation of nitre, the manufacturing of acids, salts, &c., are all results of pure chemistry. Take gunpowder as a specimen ; no person but a man infinitely diversifying his processes and guided by analogy could have made such a discovery. Look into the books of the alchymists, and some idea may be formed of the effects of experiments. It is true, these persons were guided by false views, yet they made most useful researches; and Lord Bacon has justly compared them to the husbandman, who, searching for an imaginary treasure, fertilized the soil. They might likewise be compared to persons who, looking for gold, discover the fragments of beautiful statues, which separately are of no value, and which appear of little value to the persons who found them; but which, when selected and put together by artists, and their defective parts supplied, are found to be wonderfully perfect and worthy of conservation. Look to the progress of the arts since they have been enlightened by a system of science, and observe with what rapidity they have advanced. Again, the steam engine in its rudest form was the result of a chemical experiment; in its refined state, it required the combinations of all the most recondite principles of chemistry and mechanics, and that excellent philosopher who has given this wonderful instrument of power to civil society, was led to the great improvements he made, by the discoveries of a kindred genius on the heat absorbed when water becomes steam, and of the heat evolved when the steam becomes water. Even the most superficial observer must allow in this case a triumph of science, for what a wonderful impulse has this invention given to the progress of the arts and manufactures in our country! how much has it diminished labour, how much has it increased the real strength of the country! Acting as it were with a thousand hands, it has multiplied our active population, and receiving its elements of activity from the bowels of the earth, it performs operations which formerly were painful, oppressive, and unhealthy to the labourers, with regularity and constancy, and gives security and precision to the efforts of the manufacturer. And the inventions connected with the steam engine, at the same time that they have greatly diminished labour of body, have tended to increase power of mind and intellectual resources. Adam Smith well observes that manufacturers are always more ingenious than husbandmen; and manufacturers who use machinery will probably always be

found more ingenious than handicraft manufacturers. You spoke of porcelain as a result of accident; the improvements invented in this country, as well as those made in Germany and France, have been entirely the result of chemical experiments, the Dresden and the Sèvres manufactories have been the work of men of science, and it was by multiplying his chemical researches that Wedgwood was enabled to produce at so cheap a rate those beautiful imitations, which, while they surpass the ancient vases in solidity and perfection of material, equal them in elegance, variety, and tasteful arrangement of their forms. In another department, the use of the electrical conductor was a purely scientific combination, and the sublimity of the discovery of the American philosopher was only equalled by the happy application he immediately made of it. In our own times it would be easy to point out numerous instances in which great improvements and beneficial results connected with the comforts, the happiness, and even life of our fellowcreatures, have been the results of scientific combinations; but I cannot do this without constituting myself a judge of the works of philosophers who are still alive, whose researches are known, whose labours are respected, and who will receive from posterity praises that their contemporaries hardly dare to bestow upon them.

A CHEMICAL TEA LECTURE.

In-fu'sion, n. (L. fusum, see fundo).
De-coc'tion, n. (L. de, coquo).
Mac-er-a'tion, n. (L. macer).
Solu-ble, adj. (L.solūtum, see solvo).
E-vap-o-ra'tion, n. (L. vapor).
Ex-ha-la'tion, n. (L. ex, halo).

("Evenings at Home.")

| Sat'u-ra-ted, adj. (L. satis).
Vol'a-tile, adj.(L. volātum, see volo).
Extract, n. (L. ex, tractum, see
traho).

Con-densed', adj. (L. densus).
Dis-til-la'tion, n. (L. stilla).

The meanings of these words will be found in the lesson.

TUTOR. Come: the tea is ready. Lay by your book, and let us talk a little. You have often assisted in making tea, but perhaps have never considered what kind of an operation it is. PUPIL. An operation of cookery, is it not?

T. You may call it so; but it is properly an operation of chemistry.

P. Of chemistry! I thought that that had been a very deep sort of a business.