They will be described by the scientific members of the Institution, and their uses and advantages pointed out, and the specimens exhibited to the public in its mu

seum.

You are respectfully requested to bring with you, on your return, such specimens as you may collect during the ensuing recess. Even a single specimen from each member will be of great advantage to the Institution, and be thankfully received as a tribute to science.

We have the honor to be, sir, your most obedient servants,

J. R. POINSETT,
J. K. PAULDING,

To the Hon.

Directors.

A letter was read from Lieutenant W. D. Porter of the United States Navy, dated the 17th January, 1840, and was referred to the Directors, who were requested to carry into ef fect, if in their power, its suggestions.

Extract from Lieutenant Porter's letter.

"The Army and Navy could be made beneficial to the Institution. There are many in both branches who would, no doubt, employ their leisure in obtaining specimens and information, provided they were directed in the right way. A cabinet could be placed on board of all our sea-going ships under the charge of the commander, in which might be deposited specimens by all persons desirous of making donations, to be finally sent to Washington. By such an arrangement the society would receive duplicates which might be presented to the colleges and museums of the country. Cabinets at all the army and naval depots might in the same way be made highly useful. The donors and collectors would feel themselves amply rewarded by knowing they were aiding in the diffusion of useful knowledge in their country."

Information has been received that about 150 boxes, the results, as far as have been received, of the Exploring Squadron's exertions, containing a variety of interesting objects of Natural History, and destined for the cabinet of the Institution, have been shipped at Philadelphia, and are expected as soon as the navigation opens. In consequence of the statements contained in the following communication, the specimens will not be handled until all the necessary arrangements shall have been made:

"It would be unadvisable to break open the cases containing the articles collected by the South Sea Exploring Expedition, until such period as they are intended to be prepared for exhibition. This refers to the zoological and ornithological department principally.

"The immense quantity of arsenic, and corrosive sublimate, necessary for their preservation requires imperatively that very great caution should be observed, and that the handling and arrangements should be under either the immediate inspection or personal attention of one fully adequate to all the details connected with this subject.

"In the hands of inexperienced persons death might be the result.

"PHILADELPHIA, February 6, 1841." The following letter from Captain George W. Hughes, of the corps of Topographical Engineers, has been received:

BRUSSELS, January, 1841. TO FRANCIS MARKOE, Jr. Esq., Corresponding Secretary of the National Institution for the Promotion of Science, Washington.

SIR: Availing myself of a season of comparative leisure, I have transcribed, for the National Institution, that portion of my journal which relates to a tour through South Wales; which will be followed in a few days, by a copy of the notes taken in Devon and Cornwall, with some general remarks on the working of the tin and copper mines, and the preparation of the ores for market.

You will perceive that the journal is not in continuation of that previously transmitted, but, if I should find leisure before the season for travelling opens, I may attempt to supply the omission by papers on several subjects of scientific and practical interest.

I have the honor to be, sir, your obedient servant

GEORGE W. HUGHES.

December 30, 1840.-Left London by the twelve o'clock train for Bristol on the "Great Western railway," intending to visit the mineral and manufacturing regions of Wales, Devon, and Cornwall. The great western is open from London to Worton Bassett, 60 miles, and also from Bath to Bristol, 12 miles-the intermediate distance being travelled in post coaches owned by the railway company. The gage or distance between the rails is 7 feet; the gage of the other railways being 4 feet 8 inches. This is admitted to be one of the best constructed roads of the kind in the world, and nothing can be more smooth, easy, and rapid, than the transit of the carriages over it. As this railway is peculiar in many respects, I may make it the subject of a special communication at some future period. Mr. S. K. Brunell, the chief engineer, has laid a wager, I am informed, to run an engine over the entire line when finished (112 miles) in two hours, which it is believed he will accomplish, as engines have been run on the road at quite as high a velocity. Some time since a train conveyed Prince Albert from Windsor to the Paddington Terminus at so frightful a rate, that he was "graciously pleased," as the newspapers state, "to command that they should not in future carry him at a greater speed than 25 miles an hour." Much amusement was excited at the time by a remark of George the third, (before railways were,) that he was not fond of rapid travelling; 16 miles the hour was fast enough for him or any other reasonable person. 4

December 4th.-Bristol is a fine old town, of much capital and former trade, having been the second city in the kingdoms; a rank which it has long since forfeited owing to the want of enterprise in its inhabitants, who, to do them justice however, are now straining every nerve to regain their former ascendency, as is evinced by the various important projects on which they are engaged, such as transatlantic steam-navigation—the Great Western railway-the Exeter railway and the magnificent suspension bridge over the Avon, one of the wonders of the world.

Remained here all day and dined in the country with Mr. Webb Hall, an eminent agriculturist and breeder of fine cattle; the vicinity of Bristol is eminently beautiful and in a high state of cultivation. The town is built on both sides the river Avon, and the basin is formed by two locks abreast, retaining the high-tides which rise about 12 feet.

December 5.-Left at 10 o'clock for Swansea in a steamer-a very calm and foggy day, so that we could see scarcely the length of the vessel ahead. The ride down the Avon is in fine weather very beautiful, but the navigation is difficult at all times, owing to the narrowness of the channel and to the numerous craft passing to and fro. Nothing but the minute and judicious regulations established for the guidance of vessels and the rigid enforcement of them, prevent the frequent occurrence of serious accidents. Just below the locks is the site of the chain suspension bridge (already mentioned) of a single span measuring nearly 700 feet, at an elevation high above the masts of the largest ships. The towers are finished and one chain stretched across, (on which persons are carried in a car,) and the whole is expected to be completed in the course of the year 1841. Mr. Brunell is the Engineer, and this work, like every thing he touches, bears the impress of his boldness in design and skill in execution.

We reached the mouth of the Swansea river (called the Mumbles") about 8 o'clock at night, but it being low tide, could not ascend to the town till after midnight. The access to the harbor is still difficult, notwithstanding the large sums of money expended for the improvement of the navigation, and on the construction of artificial piers, which have, however, much ameliorated its condition. The spring tides rise here frequently fifty feet, and, at low tides, there is no water in the channel. At the principal obstruction there is a light-house, and one also at the Mumbles; and a large bell is rung when there is just ten feet water on the bar, whether at flood or ebb. The British Government is very liberal in making provision for the light-house establishment, and bestows much commendable attention upon this important subject, which might, with great propriety, be imitated elsewhere.

6th December.-Visited the extensive copper works of Williams, Forster, & Co. Young Mr. Williams, the son of the managing proprietor, showed me over the works, and communicated, without reserve, the most particular information In reference to the various processes by which the ores are reduced to a metallic The domestic ores are brought to Swansea pulverised, but the foreign ores frequently in their natural condition; the preparation at the mines of the ores for

state.

working is a tedious and rather laborious process, but a description of the manner of doing it will properly come within my account of the Cornwall and Devonshire mines. It is a great economy to have the ores submitted to this preliminary operation before shipment, as it induces, among other advantages, a very considerable saving in freight; and is, in fact, absolutely essentia! to the successful working of the poorer ores.

The ore, having been pulverised, is carried by railway and steam power up to the Hoppers, from whence it is passed into the furnaces, (below the Hoppers,) and there subjected to a high degree of heat, for twelve hours, by which time it is well calcined. This drives off much of the arsenic and sulphur with which it is combined. It is then carried to another furnace, where it is melted. The slag is lighter, floats on top, and is the first drawn off. Fluxes are seldom necessary, and never so, except with a very refractory ore, when fluate of lime is used for that purpose. The first slag, which is usually remelted, generally acts as a sufficient flux of itself. It is often seen crystallized in various forms, exhibiting a beautiful pavonine play of colors. The crude copper is now broken up and remelted, with a current of air passing through it for the purpose of oxidising the iron with which it is mixed, and is then drawn off, into a tank of cold water, to granulate. The water is prevented from becoming hot by a cold stream continually running through the tank. The object of the granulation is to separate the metal into small globules, so that the fire may circulate freely through and amongst it, when again subjected to its purifying action. After granulation it is again roasted or calcined for thirty hours, and is then removed to another furnace, when it is melted, with a draft of air passing through it, as before, to effect a still further oxidation of the iron; from this furnace it is drawn off and run into pigs. It is then again broken up, remelted, and, in a fluid state, conducted into a refinery, among burning charcoal, from whence it is run into ingots, or into plates about 18 inches square by two or three inches thick. This is sometimes the copper of commerce; but it is usually rendered malleable and ductile by the following processes, viz: it is clipped, heated, and rolled, and cut into sheets, say two feet long; again heated and rolled; then again heated, doubled, and rolled, and sometimes (depending on its quality) again rolled, without additional heating.

This is called finishing: it is then immersed in a bath of uric acid for the purpose of brightening the metal, and removing the appearance of impurities from the surface. It is then put into a furnace; then immersed in cold water, from which it is brought out bright. It is then taken to a machine, where its four edges are clipped smooth, leaving it about three feet long and one wide, in thin sheets. It is then assorted, weighed, and stamped with the weight per square foot, which ranges from 10 to 20 ounces.

In some of the establishments, the processes are more simple; but I should doubt these being so efficient. As, for instance, the metal is granulated from the first melting, direct, and after the second melting it is not broken up, but remelted in mass; and, in rendering it malleable, it is not always submitted to so many heatings and rollings. At Mr. Williams's works, an engine of 96 horse powe

performs the necessary mechanical labor of the establishment. The smoke of all the furnaces is conducted by flues to a large brick arched trunk, or common recipient, which leads to a chimney about 70 feet high; this discharges the smoke and noxious vapours, and relieves the workmen from much of their baleful influence.

In the vicinity of the works, and, indeed, for miles round, there is scarcely the appearance of vegetation, and, in many places, not a trace of it can be seen. Every thing seems to droop and to die under the deleterious influence of the noxious gases emitted from the numerous furnaces: and where the surface of the ground was formerly covered with a rich sward, it is now furrowed by the action of the rains, and nothing can be made to grow on it.. It is alike inimical to animal life. Horses and cattle are poisoned by it; their limbs become swollen; their eyesight defective; their teeth drop out; and they would soon die if they were not removed at the end of two years, when their places are supplied by other victims. It is not so fatal to human beings, as they only breathe the arsenic and sulphur, while the poor beasts eat those substances from the herbage, on which they are deposited; but that it is extremely prejudical to man there can be no doubt, although he is certainly less affected by it than one might suppose. I always felt extremely uncomfortable after my visit to the works, and imagined myself pretty well poisoned; and, indeed, how could it well be otherwise, when the presence of arsenic, to say nothing of sulphur, was so perfectly obvious from its alliaceous smell? All suffer from it perceptibly, except the operatives, who are so laboriously employed as to excite profuse perspiration, which relieves them, in a great measure, from its injurious action.

Swansea is the greatest manufactory of copper in the world; and here nineteentwentieths of the copper of the kingdoms is made. All the ores here reduced are brought from a distance-some from Valparaiso, some from Cuba, a small quantity from New Orleans, and a large proportion from Cornwall and Devon, and some, but not a great deal, from Holly head, Anglesea, and from Ireland. It is now 250 years since the first ores were shipped from Cornwall to Wales. The Cuba and South American ores yield about 20 per cent., sometimes, but rarely, 25. The Irish 10 to 12, and the Cornish 7 to 84. I could learn but little about the ores from the United States, except that they were pretty good. Ores yielding 20 per cent. of copper are worth at the furnaces, when prepared for smelting, from £18 to £20 per ton, or betwen $90 and $100 per ton of 2lcwt. The best metal is worth from £100 to £120 per ton, and the profits are said to be large.

The following table (extracted from the official report of Mr. De la Beche, director of the Ordnance Geological Survey) of the foreign and British ores, sold at Swansea, by ticket, in the manner practised in Cornwall, may be useful in showing the amount of foreign copper ore imported into South Wales during the year, (ending 30th June, 1838;) as also the produce of some of the copper mines in Ireland and Wales, for the same time: