been made, they had not been made officially; and the following is a copy of the report upon the experiments made March 8th and 11th, 1837 :

The above tests were perfectly satisfactory, and considered surprising by the naval gentlemen present on the occasion. The experiments were made twice over by the government officers, and the results almost exactly alike. From a want of knowledge in naval men respecting the properties of materials, it was found difficult to convince them of the why and wherefore of the superior strength, &c. of a rope made from iron wires, and with the view to explain the effect of the alteration of the form of the material and the influence on its strength, a further test was made; the results of which were considered highly satisfactory by those who before had some difficulty in comprehending the cause of the superiority of the wire.

In 1838 considerable progress had been made in the introduction of the patent wire ropes, especially among the shipping interest; in the mining districts, it was being gradually introduced.

The Admiralty appear to have adopted it in the navy, and taken it up in earnest; various experiments, tests, and reports were made by their orders, and in the beginning of the next year they had several vessels fitted.

In March, 1839, Mr. Andrew Smith obtained another patent for his invention of certain improvements in the manufacture of ropes, &c., which invention applies to that mode or method of making or manufacturing ropes, cords, or cable, in which several strands of material are twisted or coiled one round the other, as is the usual method of making ropes, cords, or cables of hemp or other fibrous materials.

In addition to the various tests to which the wire rope was submitted, and the results given, the following table was prepared for the Lords Commissioners of the Admiralty, and embodied in a report to their Lordships :*Splice drew.

A TABLE showing the comparative merits between Hemp and Wire Rope as applied to the different class ships of her Majesty's Navy, as regards Price, Weight, and Size, the strength of each, as proved by the testing machine and by experience, being equal.

The great advantages arising from the use of wire rope instead of hempen rope, are its being stronger for the same size in hemp, or lighter and smaller for the same strength, cheaper first cost, and more durable, more difficult to cut, and therefore not subject to the serious and most sudden danger to which hempen ropes commonly expose life and property in mining operations.

It is scarcely necessary to recite instances of accidents arising from this cause in the coal and iron districts of this country; they have been of so frequent occurrence, as the pages of the Mining Journal afford abundant evidence.

An objection having been raised to the wire rope "breaking off short without warning," the following experiment, which took place at the Iron Chain Cable Works of Mr. Lewis at Withymoor, near Dudley, July 25th, 1840, is reported by that gentleman :—

It will be seen by the above, that instead of breaking short, like chain or hempen rope, it took three separate strains to break it entirely.

Mr. Matthias Dunn, a gentleman well known to the scientific world in connection with practical mining affairs, and whose talent and ability as a mining engineer stand pre-eminent, speaks of the merit and value of wire rope, at this time, in a letter to the editor of the Mining Journal, in a manner which must be at once conclusive as to its merits.

The next point of any interest in connection with this subject is the enrolment of Mr. Newall's specification in February, 1841, and its publication in the following month. The only feature of novelty in this patent appears to be a very ingenious arrangement of machinery for making wire rope, whereby the operations of forming the strands and laying up, hitherto done by two machines, are by his done at one and the same time, and in the same machine, thus effecting a great economy both of time and room, and a certainty of uniformity in the laying or twisting of the rope.

The machine consists of a great many parts and numerous toothed-wheels and gearings, some of which must revolve at a very high velocity, and may in this respect be faulty and liable to derangement; but on the whole, if the machine can be made to work correctly and economically, it will doubtless be of much importance for manufacturing ropes with a limited number of wires (36).

What is claimed in this patent regarding the wire being without twist in itself, and the introduction of a core into each of the strands, and into the centre of the rope, in the process of manufacture, is not peculiar to this patent, and is not new, it having been the practice since the time when wires

were first laid into strands and ropes, to prevent the wires being twisted or "wrung."

As to six-strand rope with hempen hearts or cores, which he claims as exclusively his invention, it certainly appears there is no novelty in that. Ropes of six strands with cores, as made by Mr. Andrew Smith, were tested by that gentleman certainly in 1839, if not before; but they appear to have been sold and in use at the end of 1839 and beginning of 1840.

The other improvement claimed by Mr. Newall in his patent, is from a mode of fitting or fastening the wire rope, which appears to be original for the purpose.

It does not appear that Mr. Newall in this year made and sold any wire ropes under his patent, although he is understood to have been making extensive preparations for doing so. A large machine upon the construction described in his patent was in course of manufacture at Dundee, and it is understood that it had to be abandoned, great difficulty having been fonnd in getting the machine to work at all; and in the end the machine was altered altogether in its arrangement and mode of working.

In July, 1841, several experiments were made at Messrs. Brown, Lennox, & Co., Chain Cable Works, Mill-Wall, on the 21st July, and at her Majesty's dockyard at Deptford, on the 27th July. The ropes were Mr. Andrew Smith's patent, and were pieces of the rigging of a vessel which had been fitted some time. The tests were made with a view to show the comparative strength of the different kinds of rope.

In the same year a patent was obtained in Belgium by Mr. Lewis Goens, for making flat ropes of iron wire; they are described as being exactly like those which had been in use in this country since the year 1836.

In the same year (1841) a patent was obtained by Mr. John Baptist Freed Wilheim Heiman, of Ludgate-hill, for improvements in the manufacture of ropes and cables. The specification describes a plan of making wire rope, in a long rope-ground, by stretching a number of wires to the length required, and laying them together by means of a machine on a sledge, something similar in its action to a common rope-jack, but having a large drum, on which the rope is wound up as it is made, at one end, and at the other, a machine having six drums of smaller size, whereon the strands are wound and given out from, according to the length of the rope required to be made. The wire and strands are borne up at different points along the rope-walk by frames, and the whole is laid together much in the same way as common hempen ropes.

The preceding observations, which have been carried to an unexpected length in treating on the various patents, will doubtless be read with interest; and affording evidence of the several improvements made, and the advantages attendant on the use of wire rope, it is to be hoped will lead to its further introduction and application as tending to the security of life and property, while its economy in weight and cost, as well as its lasting properties, will be readily acknowledged.

IMPROVEMENTS IN GENERATING STEAM AND EVAPORATING FLUIDS.

BY THE EDITOR.

THE importance of any invention by which increased power is obtained, or a saving effected in the fuel consumed, is one which must be hailed as a grand desideratum by the miner and manufacturer. When it is considered the vast consumption of coal, even in the counties of Cornwall and Devon, any saving, however slight, whether arising from improvements in machinery, or any other mode whereby fuel is saved, is a matter of importance. The average quantity of water evaporated by 1lb. of fuel we believe does not exceed 7 lbs., while by a patent lately secured by Mr. Wright, from 11 to 12 lbs. of water have been evaporated, or 75 per cent. over the ordinary power obtained, while one of the main advantages attendant on this invention is that of the reduction in the cost and weight of the boilers employed, not to advert to the saving of coal. That the economy observed can be fully carried out we believe no question exists, inasmuch as an engine with boiler, and cellular plates communicating with the boiler, as described in the patent, has performed a duty approaching to upwards of 12, and this in the presence of some of the first engineers, under the direction of Messrs. Galloway, Armstrong, and others.

The claims put forth in the patent consist of the principle or mode of construction and application of tubes, and a particular kind of cellular vessels or plates, charged with water or other fluids, whereby heat may be transmitted to the interior of steam-boilers or tanks containing water intended to be boiled or evaporated. The system of evaporation pursued is that of the circulation of hot water through small tubes, or an endless tube, whereby the water in that portion of the tube is expanded and ascends. The water so contained is capable of being raised to a temperature of 400° to 500° Fahrenheit without forming into steam, thus putting the contents of the coil in motion, the heated water passing through the vessel or boiler and giving out a portion of its heat, then descending by its gravity it returns to the fire and takes up another charge, and, to use the words of the patent, "thus every particle of the water successively becomes the recipient and transmitter of caloric from the fire to the fluid to be boiled or evaporated." It is proposed that the tubes in the cellular plates or vessels shall be of iron, gun-metal, or suitable alloys, as the flame can only impinge on the boiler by passing through the interstices of such cellular vessel.