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establishments is estimated at $10,000,000, and their estimated produce for this year-valued at $75 per ton-amounts to $12,000,000. Viewed as an object of national wealth, it will be perceived that much the greater portion of this sum is a clear gain to the people of this country. For by reference to the statement to which we refer, it will be seen that but a very small proportion of the elements constituting this value of $12,000,000, could have been exchanged for foreign iron at any price. By the operation of these mills, iron ore, coal and limestone, articles of scarcely any appreciable value in a commercial point of view, are converted into useful, substantial wealth, imparting vigor and stability to every branch of industry, and preventing the exportation of the precious metals in exchange for the products of similar materials abroad.

But why should we multiply facts and arguments when we have reason to apprehend that a majority in Congress have already resolved in their hearts to abo'ish the duties on iron to be used in the construction of railroads ? But few public men, as we are constrained to believe, aspire to be statesmen. Empiricism in legislation seems to have usurped the place of statesmanship, and our best protection against an unwise, and perhaps a ruinous course of legislation is the conflicting interests and prejudices of different parts of the country. We can imagine how hard it is for an American legislator to rise ertirely above these influences, and take a clear, disinterested view of any subject relating to the industry and commerce of the nation; and therefore we admonish the friends of this measure that they are treading upon dangerous ground. If it be their odject to check the production of American iron, and secure to the subjects of Great Britain a monopoly of the iron trade at their own prices, for an indefinite period, they will doubtless succeed in their design, in case their measure becomes a law. But if it be their purpose to give encouragement to the building of railroads, and profitable employment to American industry, we can scarcely imagine a scheme, tho’ devised by an enemy, which would be more certain to depress those objects, and result in injury instead of benefit.

Owners of Limestone Quarries-quarry cave-valued on a ton of rails at 13 cents.

20,800 Capitalists—use of money, interest,&c. valued on a ton of rails at $1,50 240,000 Transportation Companies-clear profits over and above working expenses, valued on a ton of rails at $3,78..

604,800 Storekeepers and others, for merchandize, oil, brass, fire-brick, &c., valued on a ton of rails at $1,39...

382,400

Total

$1,919,60

ARTICLE II.

[From the Magazine of Art.] Manufacture of Gutta Percha.

The following remarks from an English periodical, upon one of the most useful articles recently discovered, and applied to an immense variety of purposes, will, we doubt not, be read with interest:

We live in eventful times ; and every day brings to light some new discovery in science and the arts; or some special application of hitherto known but unappreciated agents. Here, a flash of the electric spark conveys intelligence from point to point, over mountains and through the very sea itself; there, the discovery of a new law in nature robs romance of half its charms, and explains, in part, the dreamy superstitions of our ancestors; everywhere the mind of man is active and awake, and ready to receive new impressions. Indeed, one of the most remarkable characteristics of the age in which we live is an inquiring spirit, which, in some cases, amounts almost to blameable credulity. Within the memory of living men, steam and gaslight, electricity and galvanism, photography and mesmerism, were unknown agencies to the great mass of the people; and it is only within the last ten years that the substance called "Gutta Percha” has become a useful appliance in domestic life.

We purpose to record briefly the history and uses of this curious vegetable gum. Let us glance at the

GUTTA PERCHA IN ITS NATIVE WOODS. Like photography and the new planet, this product seems to have had more than one discoverers - Dr. Montgomerie, assistant surgeon to the Presidency at Singapore, and Mr. Thomas Lobb, botanical agent to the Messrs. Veitch, the well-known florists of Exeter, each claiming the discovery as his own, though each was miles distant from, and acting independently of, the other. Priority of discovery, however, seems by common assent to be given to the first-named gentleman. The home of the gutta percha tree is in the islands of the Indian Archipelago, where there is reason to believe that it is indigenous. In the year 1824, Dr. Montgomerie was out in the woods at Singapore, when he observed, in the hands of a parang, or native woodsman, a hatchet, the handle of which was composed of a strange substance. "I questioned the workman, in whose possession I found it,” says the Doctor, in his account to the Society of Arts, “and heard that the material of which it was formed could be moulded into any form by dipping it into hot water, when it became as plastic as clay, and when cold regaining its original hardness and rigidity." Subsequent inquiry led to the fact that gutta percba, like caoutchouc, or india-rubber,

is the sap of a species of saponaceous forest tree, thousands of which abound in the dense forests of the Malay peninsula.

Of course, the Doctor was not long in disseminating his knowledge of so remarkable a substance. He speedily procured specimens of the tree and its product in various states of preparation, and forwarded them to the Society of Arts in London. As soon as it arrived in this country, its peculiar properties were rigidly inquired into; and, its value in manufactures being speedily ascertained, the gold medal of the Society was awarded to the Doctor as the first discoverer.

This substance derives its name, not from the scientific worldthough it is curious that the first half of the term is the Latin word for drop, whence it might be concluded that gutta percha meant the droppings of the percha tree -- but from the native Malays. It is pronounced pertsha, not perka.

Dr. Montgomerie had several opportunities of becoming acquainted with the method by which the gutta or sap was obtained from the tree. The fruit yields a “concrete and edible oil, which is used by the natives with their food;" while the sap circulates between the bark and wood of the tree in vessels whose course is sufficiently well marked by black longitudinal marks. At first the natives were in the habit, when they required a supply, of felling the tree; but experience soon taught them that the milky juice might be collected by cutting notches here and there in the trunk, and that in this way the life of the tree might be saved for future (tappings.” The sap coagulates in a few minutes after it is collected; but before the crude gum becomes quite hard, it is kneaded by hand into compact oblong masses from seven to twel e inches in length, by four or five in thickness. This part of the work is mostly performed by women. The blocks made up for exportation, however, are not always of uniform size and appearance, the fancy of the rude barbarian sometimes giving them strange forms -such as that of a bird with red berries for eyes, images of ships, quadrupeds, or the "human face divine.” The gum is always sold by weight-a fact which is taken advantage of by the crafty savage, who, in humble imitation of more clever adulterators, sometimes introduces a stone or a heavy substance into the interior of the mass.

As it would entail a serious loss of time on the mer. chant if he were to cut each block at the port of shipment, it often happens that, on the substance reaching this country, it is found to conceal stones or rubbish ; and then woe to the purse and the cutting-knives of the purchasers! Besides this, however, the block often contains a vast amount of unavailable material in the shape of bark, dirt, leaves, and so on, which become accidentally incorporated with the gum.

From the examination of the specimen sent over by Dr. Montgomerie, it became apparent that a large trade in the article would speedily take place; and in a few months the jungles of the Johore Archipelago, in scene of the first gatherings, were explored by Englishmen, Chinese, and Malays, in search of the gum-exuding tree. Their efforts were actively seconded by the natives ; and in a short time it was discovered that the supply, of which some doubts had at first been entertained, was almost inexhaustible. It is singular, remarks an acute observer, that, although the Portuguese, Dutch, and English, had, one or other of them, retained possession of the islands on which the trees grow for more than nine centuries and a half, it should have remained for an Englishman to discover their valuable properties at so late a date as 1843.

The rise of this new trade gave a great impulse to the activity of the Oriental islanders; and the value of the gum becoming fully known, eager search was made from island to island, and among the forests of the Archipelago; and large profits were made by the sarmingongs, or chiefs, of the aboriginal tribes, who exacted from the gum hunters a royalty on all they found.

Sufficient profit, however, was left, even after this deduction, to stimulate the cupidity of the ratives, and the port of Singapore was speedily supplied with the article in great quantities. At present, above two millions of pounds are exported into this country in the many. shaped masses alluded to. We will now inquire into

THE NATURE AND APPLICATIONS OF GUTTA PERCHA. At the present time the chief supplies of the article come from Singapore, though vast numbers of the tree-the wood of which, being of a soft spongy nature, is of little commercial value found in Borneo, Java, Sumatra, and Penang. In its nature it differs from indian-rubber chiefly in its superior density and toughness. Though both substances are somewhat alike in appearance and manner of application, the absence of oxygen in indian-rubber may account for its greater elasticity. The chemical constituents of gutta percha, as ascertained by Dr. Maclaghan, areCarbon....

86.36 Hydrogen......

12:15 Oxygen

1:49

-100
While those of india-rubber are
Carbon......

87.2
Hydrogen.....

12.8

-100 Exposed to a temperature of 248 degrees, gutta percha melts ; and in cooling remains in a semi-fluid adhesive state - partially decomposed, in fact; and when set on fire it burns very readily, with a dense smoke. At a temperature of about 200 degrees it becomes soft and ductile, though without stickiness, and can be put into the shape it is intended to retain when cool. Its specific is -975, that of water being 1.000. It is a repellant of, and completely unaffected by, any description of cold water; and of heat

are

.

and electricity it is a non-conductor. It is proof against alkalies and acids, being only affected by sulphuric or nitric acid in a highly concentrated state; while the most powerful ascetic, hydrofluoric, or muriatic acids, or chlorine, have no effect whatever on its structure or capabilities. Of its power to resist frost, sufficient proof exists in the number of boot and shoe-soles manufactured from it; and of its acoustic properties we shall have more to say.

The capabilities of the resin were tasted as soon as the specie men forwarded by Dr. Montgomerie reached London, and a kind of historical interest is attached to this sample from the fact that, from this humble beginning, a large branch of manufacture has arisen which now employs some thousands of workmen. Several ingenious tests were applied to the specimens, and it was soon proved, by Messrs. Whishaw and Hancock, that it was applicable to a vast number of purposes; and from it were made tubing, lathe bands, and impressions of medals—all of which were shown at the late Exhibition in Hyde-park. If further proofs of its value were necessary, we need only refer to the experiments made by these gentlemen; one of which consisted in the softening a mass of the material in hot water, pressing it round a soda-water bottle, hardening it in cold water, pressing it out into a thin sheet, and then, by the application of heat, again rolling up the gum into the form at first assumed. From the patents taken out by Messrs. Han. cock, arose the manufacturing and trading firm known as the “Gutta Percha Company.' We will now examine

THE MANUFACTURE OF GUTTA PERCHA. Perhaps few of our readers think what a vast amount of capital and labour are constantly working hand in hand in the byways of London. We

pass through the main streets, and are acquainted with the general complexion of the thoroughfares right and left, but, unless our business leads us directly into the vortex of industry, we bestow little thought upon aught that comes not immediately before our eyes. A few steps out of the main line in one direction take us into the midst of the tan-yards of Bermondsey ; a hundred yards or so from Finsbury-square, and we are in a new world among the weavers of rich silken and velvet stuffs; through a street or two from that same square, and we are deafened by the clang of hammers and the din of labour; in every direction, did we care to search, we should find factories where hundreds of men earn the “daily bread” for which, it is to be hoped, they nightly pray. So it is with the spot in which the Gutta Pereha Company have their factory, A few yards out of the City-road, near the canal basin, and we find ourselves in a strange neighbourhood, where coals, and lime, and culm, and building materials, are being constantly unloaded from queer-shaped vessels, and were numerous manufactures are being carried on. In this “Wharf-road" are the works we are now visiting.

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