with the remarkable contrast presented to them in the “BalMaidens," as they are locally called, of the Cornish mines. The kind of labour which they are called upon to perform is such as produces fine muscular development; and as they work principally in the open air, the appearance of robust health is remarkable in all-as is also their cleanliness. On the Sunday these young females display a large share of womanly fondness for dress; and they may be seen gaily apparelled, a cheerful, happy race, gathering either at church or meeting-house. One thing alone is to be regretted the demand for labour of this kind induces parents to take their children from school at too early an age, and the girls being employed at the mines until they are married, know little of domestic economy-the husband's home is less comfortable than it should be, and the children are as imperfectly trained as the parents themselves have been. The attention of the landed proprietors is now being drawn to this evil, and we may hope for some improvement. A mining school of a superior class is now established at Truro, and the intention of its projectors is, that a series of primary schools shall be organised in connexion with it in all the great mining centres.

The ore being drawn to the surface and dressed for the market, it may appear our task is finished. But there are a few particulars connected with the sale and reduction of the copper ore which are sufficiently curious to claim a short notice.

All copper ores, except a few very small parcels disposed of by private contract, are sold at a public "ticketing." This must be described. The mines having ores for sale notify this to the Clerk of the Ticketings, and this is published on the ticketing papers. The smelters then send their agents to the mines, and they take a sample from each pile of ore which has been previously weighed and numbered.

These are

An agent for the mine takes a similar sample. submitted to the assayers respectively employed, and their duty is to determine with great exactness the quantity of copper in a ton (of 21 cwt.) of the ore.

The day of public sale arrives; the particular parcel offered for sale is announced by the clerk; then the agents of the smelting companies write upon a "ticket" the prices which they offer. These tickets are examined by the clerk, and the name of the company offering the highest price is announced, they having thus become the purchasers. The sale of thousands of pounds worth of copper ore is thus carried on in silence, and the whole proceeding appears to give mutual satisfaction.

No copper ores are smelted in the vicinity of the mines; they are all carried to Swansea, since it is found more economical to take the ore-the heavier material-to the coal, than to bring the coal to it. The vessels also taking the ore to South Wales return laden with coals, which are used in the steam-engines of the mines. The processes in the copper-works are simple-they consist of alternate calcinations and fusions. By the former the volatile matter is expelled, and the metal more readily fused.

The extent of the copper-smelting operations of Swansea may be understood by the following estimate :— Not less than 15,000 persons derive their support from these works; and they are paid annually not less than 600,0007. in wages, and nearly 300,000l. sterling are circulated annually in Glamorganshire and the adjoining county, in consequence of their existence, for other expenses. The collieries receive not less than 200,000l. per annum for coal; and nearly 200 vessels, carrying on the average five men each, are engaged in the conveyance of ore from Cornwall to Wales.

In considering the question of the formation of those mineral lodes from which so large an amount of wealth is

now produced annually by human industry, we are, it must be admitted, involved in much doubt. At one period it was a favourite theory to refer them to igneous action-they were supposed to be the result of sublimation. Careful examination of the conditions of a mineral lode shows, however, that it was not possible this could have been the case. The crystalline character of the ores, and the arrangement of earthy crystals amongst them, clearly establish the fact, that all mineral lodes have been formed by slow deposits from water. It may appear that such immense masses could not have been produced unless the waters were strongly impregnated with mineral matter. If, however, we take into consideration the element of Time, it will become evident that strong solutions are not necessary.

We know that every river flowing into the sea bears away from the land, in solution, all those metals which, by exposure to the atmosphere, have become oxidized or rusted, and hence rendered soluble through the agencies of those earthy salts which all waters contain in larger or smaller quantities. The extent of this may be inferred from a statement made by a large manufacturer of silver goods in the metropolis: The water in which the men wash their hands is thrown into a tank, and the deposit formed therein is bought by the refiners, who pay the firm for the silver obtained from this source alone about 300l. a-year; this was formerly all wasted. Our Thames is constantly carrying to the ocean amidst the refuse of this large city, iron, copper, silver, gold, and tin; and these metals, by the aid of the saline constituents of the ocean, are all held in solution in its mighty waters. Certain French chemists have, by acting on large quantities of sea-water, determined the presence of all these metals in the sea.

From this water these metallic salts will be separated when they meet with the proper conditions. Of these we re

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main in ignorance-we only know that the proximity of two dissimilar rocks is necessary. Where the granite and clayslate rocks meet, or near their junctions, we find all the productive mines of copper and tin. At a distance from these junctions attempts have been often made to form a mine, but in nearly every case without success. It may be inferred that the two rocks, granite and slate,-one of which is always two degrees warmer than the other—may form a voltaic pair, and that hence we have an explanation of the phenomena we have been considering. We are too much in the habit of rushing to conclusions, and referring to electricity everything which we do not understand. The whole field of investigation is open to the inquirer; there is no branch of scientific investigation so full of novelty and general interest but it demands careful observation; and all deductions should be made with the utmost caution. In the existing rocks we discover those minerals which are so valuable to man. Man employs these, and they decay under

his hand. The rain-shower and the dews remove them from the surface of the dry land; the rivers take them into the sea. It is not improbable but that, in the deposits now taking place in the depths of the ocean, mineral veins are forming under the influence of those laws which have determined the conditions of the mineral deposits we now explore. Long and earnest investigation is required ere these laws can be manifested to man-as yet they are only known to the great Creator of the universe.

R. H.

THE STORY OF GREAT HISTORIES.

HUME'S "ENGLAND."

DAVID HUME was born at Edinburgh, April 26, 1711. He was the second son of a landed proprietor in Berwickshire, and was destined by his father for the profession of an Edinburgh advocate. But for the patient research and dry erudition of an accomplished lawyer he had no constitutional aptitude, and with all his ambition he did not aspire to the fame of a successful pleader. His turn was for letters and philosophy. With no eye of his own for the beauties of Nature, he was charmed with the exquisite descriptions of Virgil; and with few elements of the Sublime in his own phlegmatic composition, he could understand the secret of its production as described by Longinus. But Cicero, Seneca, and Plutarch, were the authors who opened up to him the path in which he determined to travel. Their speculations on morals and their beautiful pictures of virtue introduced him to a microcosm of which he felt that the wonders could never be exhausted, and in which unlimited conquests seemed only to wait for an adventurer sufficiently valiant. Human nature as it is, and irrespective of all light shed by Revelation on its history, now became his study; and, discarding his legal apparatus, and making a feeble effort in business only to abandon it, he retired to Rheims, in France, where, bringing Scotch frugality to the aid of philosophical simplicity, he contrived to live on a very slender patrimony, and found ample leisure to meditate on causation, the standard of virtue, and philosophical necessity.

This is not the place to dwell on Hume's powers as a