Sturtevant failed in executing his proposed plans, and was obliged, the following year, to render up his letters patent, or monopoly. John Ravenson, Esq. succeeded Sturtevant a. 1613, had a patent granted to Mm, wrote his book, entitled "A Treatise of Metallica, but not that which was published by Mr. Simon Sturtevant." Ravenson states, that at that time an iron work usually required from 1000f. to 1500f. to set it a-going, but that on his plan a capital of 100f. was fully adequate to commence a work. The furnace itself was to cost but 10f. except the stones, such furnace being capable of producing a ton of sow iron from each ton of pit coal. This man, however, failed in his attempts to prove the correctness of his statements, and resigned his patent. Several other unfortunate adventurers followed Ravenson in succession, who also obtained patents, failed in their undertakings, and resigned their privileges. It is a singular fact, that although pit coal was known long before this period, and great quantities of it were exported to Holland and the Low Countries, where it was used in the smith s forge, and in other manufactories that require a strong continued heat; yet in England the prejudice against its use in the manufacture of cast iron was so inveterate, that when it was first proposed and attempted, every obstacle that could be devised was thrown in its way, and none of the adventurers succeeded, until the year 1619, when Dudley had a patent, and manufactured pig-iron in a Mast furnace, but produced only three tons in a week.

He became, however, the object of jealousy to the other manufacturers, who contrived to get his patent limited from thirty-one to fourteen years, and his devoted works were destroyed by a lawless mob, urged, it is supposed, by his rivals in business. Soon after this, Captain Buck, Major Wildman, and some others, constructed air furnaces in the forest of Dean, in which they placed large clay pots (similar to those used in glass-houses) for containing the requisite preparations of ore and charcoal, the flame of pit coal being employed for heating the furnaces; and it was expected, that by tapping the pots below, the separated material would flow out. But the heat was not sufficiently intense to produce an entire separation of the metal, the pots cracked, and the scheme was abandoned. At this time iron was advancing, in consequence of many of the iron works having stopped for want of fuel. To those manufacturers, therefore, who could still be furnished with a supply of wood, the manufacture was highly profitable, and they obstinately opposed any new attempt by which the price of iron might be diminished. It was not till impelled by necessity, arising from the rapid decline of the annual growth of timber, that pit coal became an object of universal estimation. In this feeling the Hon.

Robert Boyle seems to have participated, for in his Usefulness of Natural Philosophy, published in 1663, he expresses a desire that some method could be found to make coke without the use of pots employed for that purpose, in order that it might be applied to the smelting of iron ores. Two years after this, Dudley (according to Mr. Gray) wrote his Metallum Martis, in which he states, that his father and himself had smelted iron with coke in large quantity, but that Oliver Cromwell, and some favourites of his, wishing, on renewal of the patent, to become partners, and from other political circumstances, the establishment was ruined, and it seems never to have been revived; for even so late as the year 1747, Mi. Mason says, in the Philosophical Transactions, that several attempts have been made to melt iron ore with pit coal, but he thinks it had not then succeeded any where, as no account of its being practised had been published, but that Mr. Ford did, however, then make pig iron, brittle or tough, as he pleased, from iron and coal, both of which were procured on the same spot.

The brittle or inferior quality of English bar iron, made from coke at this period, and the great expense of that which was made from charcoal, owing to the increasing scarcity of wood, was most likely the cause of the great decline in the home manufacture of iron which then took place; recourse having been had to Sweden and Russia for a supply, the importation of which on a great scale at this time commenced. The home manufacture was, however, again renewed by the general introduction of the steam engine; and this afforded the manufacturer the command of a power he had before no conception of. The small furnaces supplied with air from bellows worked by oxen, horses, or men, were given up; larger furnaces were introduced, and blowing machines, with an increase of the volume of air, for exciting a more vivid combustion. The steam engine was found particularly beneficial in those situations where there was an abundance of minerals for making iron, but a deficiency of water to supply the power. Experience also soon taught the manufacturer, that the produce of his furnace could be increased by enlarging the diameter of his steam cylinder and rendering the vacuum therein more perfect.

It was soon found, that by increasing these effects, a quantity of pig-iron could be produced from the coke of pit coal, which would be attended with an adequate profit. Owing to the small quantity of air necessary to ignite, and preserve the required heat in a charcoal furnace, the manufacturers very cautiously enlarged the dimensions of their blowing apparatus in applying it to coke; consequently much of the advantage resulting from a great blast (which is now extended to about 4000 cubic feet of air per minute) was lost. These difficulties were, however, gradually surmounted, and it appears, that before the year 1760, the coke of pit coal was in general use for blast furnaces. The iron trade assumed new vigour, and made most rapid progress, as will appear from the following statement of the total quantity of iron made in Great Britain between the years 1740 and 1827. Since the latter period, the manufacture and trade has been on the increase, notwithstanding the price has advanced.

In the year

1740,

17,000 tons

were

made from 59

furnaces.

"

1788,

68,000 tons

121

"

"

1796,

125,000 tons

"

"

"

1806,

250,000 tons

"

"

"

1820,

400,000 tons

"

"

"

1827,

690,000 tons

284

"

Of which latter quantity there

were produced -

By Staffordshire . .

. . 216,000 tons from

95

furnaces.

By Shropshire . .

. . 78,000 „

31

"

By South Wales

. . 272,000 „

90

"

By North Wales

. . 24,000 „

12

"

By Yorkshire . .

. . 43,000 „

24

"

By Derbyshire . .

. . 20,500 „

14

"

By Scotland . . .

. . 36,500 „

18

"

Total . .

. . 690,000 „ 284

"

In the foregoing statement, several furnaces in Gloucestershire, Cheshire, and other places are omitted, which will render the produce in round numbers 700,000 tons. About three-tenths of this quantity are of a quality suitable to the foundry, which is all used in Great Britain and Ireland, with the exception of a small quantity exported to France and America. The other seven-tenths are made into bars, rods, sheets, wire, etc, of which a large quantity is exported to all parts of the world. Having thus given a brief historical sketch of the rise and progress of this interesting and useful manufacture, we proceed to lay before our readers a concise account of the process by which iron is obtained from its ores, and brought into a crude or pure state, adapted to the wants of mechanics, or to the various uses to which it is applied.