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TIN

There are few of the metals possessed of the same interesting relations as the one we have now before us. The archæology of tin is more than usually attractive, and in the very dawn of history it is mentioned by the great Hebrew lawgiver as one of the metals to be purified by fire. The early inhabitants of Etruria and Central Italy were skilled in the applications of tin; the nations of the Levant were likewise accustomed to its use; but the most interesting point to us in the history of this metal resides in the memorable traffic which the Tyrian mariners pursued with the natives of the British Islands. Perhaps the whole catalogue of Phænician commerce, so eloquently denounced by the prophet Ezekiel, could yield no article of superior value to this Cornish metal; indeed, it must have been more valuable to them than the cedars of Lebanon or the gold of Ophir. There was at that period an enormous consumption of bronze, by contemporary nations, in all their instruments of art and war ; and tin-a metal of rare occurrence and limited distribution—is the most essential constituent of bronze, as we learn from Pliny. If we recollect, too, that the Phænicians possessed a monopoly of this commerce, we shall then be able to conceive the idestimable value to its discoverers of this proliric tin country. So fully, indeed, was this importance recognized, that those astute merchantmen anxiously concealed from their rivals and contemporaries the geographical situation of these “ tin islands.” But the secret at length transpired. Publius, a Roman proconsul in Spain, after several upsuccessful efforts, opened to his countrymen the treasures of this undiscovered Dorado; and all through the long period of his. tory which has since elapsed, Cornwall has continued to furnish an inexhaustible supply of the metal. The principal localities of tip are Cornwall, Bohemia, and Saxony, in Europe ; Malacca, Pegu, and Banca in Asia. Cornwall, notwithstanding its prodigious and long-continued drain is still the most prolific tin district in the world. It has been calculated by Mr. Porter and others that Cornwall yields appually upwards of 50,000 tons of the metal, the value of which varies from £400,000 to £500,000.

CLASSIFICATION OF LEATHER SKINS. The stoutest leather is made from ox-bides. Buff leather was formerly made from the hide of the buffalo, but it is now furnished by the cow-hide. Calf-skin supplies the great demand for the upper part of boots and shoes. Sheep-skins form a thin, cheap leather; lamb skins are used for gloves ; goat and kid-skins form a light leather of fine quality ; deer skins are usually shamoyed, or dressed in oil; horse-hide is prepared for harness work, &c.; and this, with seal skin. is also used for making enameled leather; dog-skin makes a thin tough leather, but most of the gloves sold as dog-skin are made of lamb.skin. Hog-skin makes a thin, porous leather, and is used for covering the seats of saddles.

In making shamoyed leather, of which washing-leather is a cheap example, the skins of deer, goats, and sheep are impregnated with oil instead of the other ingredients mentioned above. After a certain preparation the skins are beaten for many hours with beavy wooden machines, and cod oil is forced into the pores. Sheep skins, when simply tapned, are employed for inferior book-binding, and for various other purposes for which a cheap leather is required. The mock or imitation morocco, and most of the other colored and dyed leathers used for women's and children's shoes, carriage livings, and the covering of stools, chairs, sofas, writing tables, &c., are also made of sheep-skin. Lamb-skins are mostly dressed white or colored for gloves.

Japanped leather of various kinds is used in coach-making, harness-making, and for various other purposes.

Patent leather is covered with a coat of elastic japan, which gives a surface like polished glass, impermeable to water; and hides prepared in a more perfectly elastic mode of japanning, which will permit folding without cracking the surface, are called enameled leather ; such leather has the japan annealed, something in the same manner as glass; the hides are laid between blankets, and subjected to the heat of an oven at a particular temperature during several hours, until finished properly.

In making Russia leather the skins are first freed from the hair or fleece by steeping them in an ash-lye, then rinsed, fulled, fermented, and cleaned. They are then soaked for forty eight hours in a bath composed of water mixed with a paste of rye flour. The skins, when taken out of the bath, are left in tubs for fifteen days, then washed, and immersed in a boiler containing a hot decoction of willow bark, in which they are handled and pressed for half an hour. This manipulation is repeated twice a day for a week, after which the tanning infusion is renewed, and the process is repeated on the same skins for another week, after which they are exposed to the air to dry, and are then dyed and curried.

Morocco is the skin of a goat, or some other animal resembling it, called menon, and common in the Levant. It is dressed with sumac or galls, and colored with any color, and is much used in upholstery, book-binding, for ladies' shoes, &c. But most of the morocco to be obtained in this country is prepared here from sheep-skius. The name is derived from the kingdom of Morocco, whence it is supposed the manner of preparing this leather was first borrowed. Morocco is, however, brought from the Levant, Barbary, Spain, Flanders, and Russiared, black, yellow. blue, &c. The process has been latterly greatly simplified, and the brilliancy and durability of the Turkey red successfully imitated. The peculiar ribbed appearance of morocco is given by means of a ball of boxwood, on which is a number of narrow ridges. Sheep-skin morocco is

prepared from split skins, a peculiar arrangement of machine being employed for this pur. pose. Instead of stretching the skin on a drum, it is passed between two rollers, the lower one of gun-metal and solid, and the upper one of gun-metal rings ; while between the two rollers, and nearly in contact, is the edge of the sharp knise, which is moved by a crank. When a skin is introduced between the two rollers it is dragged through against the knife edge and divided, the solid lower roller supporting the membrane, while the upper one, being capable of moving through a small space by means of its rings, adjusts itself to inequalities in the membrane ; where this is thin the ring becomes depressed, avd where it is thick they rise up, so that no part escapes the action of the knife. The divided skins are not sewed up into bags, as from their thinness the can be tanned quickly.

TEMPERATURE. In man the temperature of the blood is 98°, in sheep, 102°, in ducks, 107o. During the chills of ague the heat of man's blood falls to 96° and 94°, while at the height of fever it rises to 102°, and even to 105?.

THE IRON TRADE. The London Times says that the number of furnaces in full work in 1859, in the northeastern iron district, comprising Northumberland, Durham, Cleveland, was sixty eight, or ten more than the average for 1858. The total production of last year was 620,000 tons, of which 46,934 tops were exported and 524,066 tons were used in the district, shipped coastwise, and sent away by rail. The total quantity tbus absorbed was 571,000 tons, leaving a surplus of 49,000 tons over the deliveries. The stock, December 31, 1858. was 25,000 tons, and the estimated stock at the close of 1859 was, therefore, 74,000 tons. Against these stocks of pig iron, large sales have, however, been made for future delivery. Four furnaces were completed and put in blast in the district in 1859 ; five more are now nearly ready, and six more have been begun.

The Philadelphia North American remarks, that it is to be regretted that there are not equally prompt and trustworthy returns of the American iron production at the termination of every year.

It will be seen that the average production of the English furnaces was about 9.000 tons, which, although large, is less than that of the Lehigh anthracite furnaces. These produced, in four or five instances, about 10,000 tons to the furnace during 1859. The total production of anthracite iron in the Lehigh region, in 1859, was about 135,000 tons, and in the Schuylkill about 80,000 tons, in both cases a considerable advance upon last year. In the circle of Philadelphia business, it is estimated that the production for the past year was probably 250,000 tons of pig iron, but for more distant places it is feared that the return will present a far less encouraging statement.

THE MOTION OF A CANNON BALL. The Scientific American says the latitude of New York city is 40° 42' 40"; and as the degrees of longitude diminish in length from the equator to the poles, the length of a degree of longitude here is about 52} miles, or more nearly, say 277,250 feet. As the earth turns on its axis once in 24 hours. it carries everything on its surface, from west to east, to the distance of one degree in four minutes ; so that the city of New York, with everything else in this latitude, is constantly rupning round towards the east at the rate of about 13 miles a min. ute, or, more accurately, 155 feet in a second. Now, this is just about the velocity of an ordinary canpon ball. Hence, if a candon in this latitnde is fired when pointing exactly west at a fort, the ball is simply stopped in its eastern motion---the cannon runs away from it, and the fort comes up against the ball with a crash! This refers merely to the motion of the ball in relation to the diurnal rotation of the earth ; if we attempted to ascertain the absolute motion of the ball, considering the motion of the earth in its revolution around the sun, and the inotion of the sun among the stars, we should find the problem not only very complicated, but absolutely insoluble in the present state of astronomical science ; indeed, it is impossible to conceive that we ever can have such knowledge of the universe as to enable us to determine the absolute motion of the sun

in space.

VAPOR. In a vacuum water boils at 88o. At the boiling point the vapor of water has the same dopsity as the atmosphere ; it is the same with all other vapors produced by boiling liquids.

SPINDLES IN ENGLAND AND COTTON SUPPLY, The following interesting paper by Mr. HENRY ASHWORTH, of Bolton, England, is taken from the Manchester Examiner and Times of the 29th February :

The alarm which bas recently been raised on the subject of an adequate supply of cotton, appears to have roused much attention. The discussion in the House of Lords, as well as in the Commons, and the numerous articles which have followed in the public journals, indicate a degree of interest which would appear to call for the disclosure of the following important facts :

Last year the consumption of raw cotton by the manufacturers of Great Britain was 2,296,700 bales, or 973,800,800 pounds.

In 1849, now ten years ago, it was 1,590,400 bales, or 629,798,400 pounds. The increase in the ten years having been 55 per cent, or 706,300 bales, or 344,002,400 pounds.

The above progress, when explained in the language of practical life, represents an increase of consumption, in the above period, at the rate of 70,000 bales a year, or 1,350 bales per week.

'In the next place, let us have our attention directed to the amount of increase which has been going on in our spindles.

In the year 1850, according to a Parliamentary return, there were in Great Britain (inclusive of Ireland) 20,858,062 spindles employed upon cotton, and, having reference to the annual consumption at that period of 629,798,400 pounds, it amounts to 300 pounds per spindle.

Therefore, if we apply these data to the cotton consumption of last year, viz., 973,800,800 pounds, we shall find that the manufacturing power we now possess is that of 32,460,026 spindles, showing an increase in ten years of 11,601,964, or an average rate of progress of 20,718 spindles per week, and requiring a weekly supply of 1,350 bales of cotton. M-anwhile, that is to say during the ten years in question, the principal increase of growth has been in the United States, and, large as it may appear, it has barely kept pace with the increase of demand, and the supplies held in the market have been gradually diminishing, and often reduced to a very scanty amount.

FORECAST OF THE FUTURE OF SPINDLES AND COTTON. The machinists of this country have, perhaps, never before found themselves so fully employed, and, according to information derived from them, there is now going on a greatly accelerated increase in the erection of mills, and in the extent of spinding machinery in course of preparation, not alone in Great Britain, but also in all parts of Europe as well as in the United States.

The new machinery now constructing for British account has been put down at 45,000 spindles per week, which is more than a two-fold rate of increase, as compared with the period above referred to. These will require to be supplied with their 30 pounds of cotton per annum for each spindle ; and at no distant day the increase of consumption for the new spindles alone will amount to po less than 160,000 bales per year, against a rate of 70,000 bales in the last ten years, or a future supply of 3,000 bales per week, as against the former rate of 1,350 bales. Let it also be borne in mind that the cotton manufacturers of Great Britain constitute only one-half the consumption under our immediate notice, while the other half is carried on in the various manufacturing districts of Europe and in the United States. Now, should the like rapidity of progress in manufacture be going on in these other countries, it must be obvious that an extension of growth will very soon be required of more than 300,000 bales a year.

It may be well for us to consider the practicability of raising, with the requisite speed, so large an addition of our supplies, in order to meet the growing demand ; let us, therefore, as in the former case, bave reference to what has already been done in the increase of cotton culture during the past ten years, and select for reference as to capability the United States, a country from which our manufacturers are deriving nearly four-fifths of their present supplies, and in which the capabilities of extension are known to be so ample, and the energetic character of the planters so reliable.

The average product of the crop of the United States for the years 1849-50 to 1853-54 was 2,731,830 bales. The average product of the five years, from 1854-55 to 1858-59, was 3,256,029 bales.

Taking the extremes between the first and last of the above years, the difference will be 1,754,775 bales, or a rate of progress of 175,000 bales per annum.

The fluctuations occurring from year to year are deserving of notice; they indicate the uncertainty which must ever impend over the future, though they do not materially obstruct the onward progress of success.

It will be marked that there is not avything decisive to be gathered from the grouping of these figures, representing crops ; the averages do not indicate certainty of production, and yet, amidst all the variations, there are marks of elasticity and encouragement in the prospects they hold out.

STATISTICS OF AGRICULTURE, &c.

AGRICULTURE OF OHIO. The annual report of the Ohio Commissioner of Statistics remarks :-We have now complete returns of all agricultural crops, for the State of Ohio, in three years of the last twenty; and the crops of wheat and corn in eleven years. These are enough to determine with sufficient accuracy the general aggregate of arable lands and the products for twenty years, the averages produced, and the value of agricultural labor. These facts are of the highest interest, and will stand in favorable contrast, as I have before remarked, with similar exbibits for any other country, even the most highly cultivated.

The following table presents a view of all the grain crops, with those of hay. and potatoes, for the years 1839, 1849, and 1858 :

1889.

1849. 1858. Corn...

.buehels 33,668,144 69 078,695 60,863,502 Wheat.

16,571,661 14,487,351 16,655,483 Oats.

14,393,103 13,472,742 8,026,251 Barley..

212,440 354,358 2,103,191 Rye....

814,205 425,918 874,513 Potatoes

5,805,021 5,245,760 5,000,000 Hay

.. tons 1,022,037 1,443,142 1,806,441 Buckwheat..

.. bushels 683,139 638,060 791,921 Aggregate of above exclusive of hay 72,097,713 93,902,884 84,314,941 It will be seen that the crop of 1858 was below that of 1849, and only about 17 per cent advance on that of 1839. The value of the crop of 1858 was much greater than either, and probably full double that of 1839. In this entire period of twenty years, the prices of products had been gradually but regularly rising, especially so of corn, the great staple of the State.

The above three years, however, are very far from being correct tests of an average crop, for it happened that each of these years was relatively a bad year for crops. Let us then take the years 1855 and 1857, which we have for wheat and corn, and make a proportional (as between 1849 and 1858) for the minor crops. We have then this result:-

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