Wednesday, April 30, 2008

Penny Magazine

"The Penny Magazine, published every Saturday, was aimed at the working class. It was part of the Society for the Diffusion of Useful Knowledge's program for liberal reform. for its reader, however, it was a source of information on subjects of general interest: everyday things like tea and coffee, well-known places in England, a series on animals and birds of Britain, descriptions of prsent-day manufacturing, even an American alaman and a serial of a personal account of an immigrant's problems. Poetry was published, too, and there are several illustrations in each issue."

The popularization of science is nothing new for in England [early 19th century] an attempt was made to build a bridge between the academic realm and the citizen. It was called the "Society for the Diffusion of Useful Knowledge" [SDUK--1828] and represented a potpourri of subject matter. The SDUK had a short life span and one of its most successful publication was called the "Penny Magazine" which covers geography, poetry, history, and the sciences.

From the July 18th, 1835 [No. 211] issue:



THIS very remarkable and useful substance is the only metallic body which exists in a fluid state at ordinary temperatures. If, however, it be exposed to a cold equal to about 72° below the temperature at which water freezes, it becomes solid, and if there were a climate where such an intensity of cold prevailed, the inhabitants would habitually see mercury in the shape of a heavy solid shining metal, like silver or tin. The naturalist Patrin relates, that during eight winters that he passed in Siberia, he frequently saw mercury in a solid state, from the excessive cold, especially the winters from 1782 to 1785, which he passed at Tomsk. Although that town, situated on the river Tom near its confluence with the Oby, is not so far north as Montrose, the spirit-of-wine thermometer fell, five or six times, 80° below the freezing point of water, and once as low as 85°. Pallas observed at Krasnojarsk, on the Yenisei, in lat. 56°, that is, corresponding nearly to the latitude of Edinburgh, a degree of cold equal to 87°, and he there saw mercury as solid as tin. By experiments made upon this metal when rendered solid by artificial means, it has been found to have a tendency to assume regular crystalline forms, to be malleable, and to be capable of being cut with a knife. In such experiments the tools employed must be previously rendered at least as cold as the mercury, otherwise the effect would be very much the same as if we were to attempt to cut wax with a red-hot knife. A piece of solid mercury placed on the hand causes a painful sensation like that of burning, and if suffered to remain would cause a blister. Mercury contracts greatly in bulk when frozen, for at the temperature of 47° it has a specific gravity of 13 54, whereas when solid it becomes as heavy as 15 61. It boils at a heat of 662°, or nearly three times that of boiling water, and if it be pure, it will evaporate without leaving any residuum; the vapour condensing upon the surrounding cooler bodies, coating them with a hite shining dew, which, when examined by the microscope, is seen to consist of myriads of minute globules. It expands by increase of heat, and up to the temperature of boiling water at least, or 212°, equal measures of heat produce equal rates of expansion; a property which renders mercury the best of all fluids for the construction of thermometers.
This metal is found in its pure state in mot mines where other ores of it exist; but never hitherto in such quantity as to be a special object of working. The chief source of supply is from ores in which the metal is in combination with other mineral substances, and most commonly with sulphur. It is found in combination with silver, in which case it is called by mineralogists native amalgam, and this mineral, according to the analysis of Cordier, consists of 72½ per cent. of mercury and 27½ of silver. Another ore, called horn mercury, from having such a consistence as to be capable of being cut like horn, is a compound of the metal with oxygen, muriatic, and sulphuric acids; but the most common ore is that combination of mercury and sulphur commonly known by the name of cinnabar, a name used by the Greek writer Theophrastus in his 'Treatise on Stones,' written about 300 years before Christ; and Pliny says that the word is of Indian origin and signifies blood, the ore being generally of a blood-red colour.
It consists, according to the analysis of Klaproth, of 84½ per cent. of mercury and 14¾ of sulphur. This substance, both in its natural state and when prepared artificially, is used as a red paint, being previously reduced to a fine powder, when it goes by the well-known name of vermilion. There are several varieties of ore in which native mercury, cinnabar, and horn mercury are dispersed through earthy and bituminous matter in various proportions.
Mercury may be considered, in comparison with those metals we have already treated of, as of rare occurrence, the supply of it being derived from a small number of places. The ores occur in the primary rocks, and in the older of the secondary, especially the strata belonging to the coal deposits; viz., in the bituminous shales and indurated clays, often accompanied by impressions of fishes. There are no instances on record of their being met with in the newer of the secondary strata, or in any of the deposits that lie above these.
The ores of mercury have not yet been found in any part of the United Kingdom. The chief mines are in Spain, Austria, and the country bordering on the Rhine which formed a part of the ancient palatinate. Formerly there were very extensive mines in South America. Small quantities are obtained in France, Hungary, and Sweden. The great quicksilver mines of Spain are at Almaden, a small town of La Mancha, on the frontier of Cordova, south-west of Ciudad Real, and situated in the mountains of the Sierra Morena. The prevalent ore is cinnabar, which is found in veins that traverse sand-stone and slate. The veins are from two to fourteen feet thick, sending out numerous ramifications. In some parts they swell out into much greater dimensions, even to so much as fifty feet, but this is in places where branches cross each other or come in contact. The district around Almaden has been celebrated for producing this red paint from a very remote antiquity, for Pliny states that the Greeks obtained vermilion from thence at a period which was 700 years before the Christian era. The same author says, that Rome derived annually 100,000 pounds weight of cinnabar from thence; and adds, that the mine was considered so valuable, that a door was placed at the entrance of it, the key of which was kept by the governor of the province, and it could only be opened by an order from the emperor: as soon as the quantity sufficient for the supply of Rome was obtained, the door was gain closed. We have no account, however, of the working of these mines until about the early part of the seventeenth century, when the then celebrated German miners, the brothers Fuggers, of whom we have spoken in describing the silver-mines of Guadalcanal, obtained a lease of them, agreeing to deliver annually to the King of Spain 4500 quintals, or about 460,000 lbs. of quicksilver. Nearly the entire produce of these mines was sent to Mexico and Peru, to be used in separating the precious metals from the ores by the process of amalgamation. Either from a failure of the ore, or in consequence of the strange policy of the Spanish government, which threw obstacles in the way of mining operations in the mother country, in order to encourage those in the colonies, or from some other cause, the mines of Almaden became considerably less productive for a long time; but about the end of the last century, the quicksilver-mine of Guancavelica in Peru having failed, the works were resumed with such increased activity, that the produce was raised from 6000 to 18,000 quintals annually, and not only Mexico but Peru was then supplied with this indispensable material from the mother country. Le Play, a French geologist, visited Almaden in 1833, and describes the mines as being more flourishing then than at any former period, yielding annually 22,000 quintals of mercury, or about 2,244,000 lbs. About 700 workmen are employed underground, and about 200in the operations connected with the extraction of the metal at the surface. Numerous trains of mules are constantly occupied in carrying the mercury to Seville, and bringing back in return the necessaries for the mining establishment. On account of the fluidity it cannot be conveyed from place to place without extraordinary precautions. About fifty or sixty pounds are poured into a fresh sheep-skin, from which the wool is taken off, the ends of which are tied tight, and this sort of bag is inclosed in a second skin, and that in a third, and three or four bags are packed in close well-made barrels. The mercury has very injurious effects on the health of the workmen; but notwithstanding this, and although the wages are very low, there is always an eager demand for employment, workmen coming at certain seasons of the year, in the intervals of agricultural labour, even from Portugal. The veins are so considerable, that although they have been actively worked for many centuries, the excavations do not extend more than about 1000 feet.

The Penny Magazine

Popularization of science

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