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This was the first application of the steam-engine to naval purposes, and, for the time, it was an exceedingly creditable one. Fulton, however, did not live to see the ship completed. He was engaged in a contest with Livingston, who was then endeavoring to obtain permission from the State of New Jersey to operate a line of steamboats in the waters of the Hudson River and New York Bay, and, while returning from attending a session of the Legislature at Trenton, in January, 1815, was exposed to the weather on the bay at a time when he was ill prepared to withstand it. He was taken ill, and died February 24th of that year. His death was mourned as a national calamity.

From the above brief sketch of this distinguished man and his work, it is seen that, although Robert Fulton is not entitled to distinction as an inventor, he was one of the ablest, most persistent, and most successful of those who have done so much for the world by the introduction of the inventions of others. He was an intelligent engineer and an enterprising business-man, whose skill, acuteness, and energy have given the world the fruits of the inventive genius of all who preceded him, and have thus justly earned for him a fame that can never be lost.

Fulton had some active and enterprising rivals.

Oliver Evans had, in 1801 or 1802, sent one of his engines, of about 150 horse-power, to New Orleans, for the purpose of using it to propel a vessel owned by Messrs. McKeever and Valcourt, which was there awaiting it. The engine was actually set up in the boat, but at a low stage of the river, and no trial could be made until the river should again rise, some months later. Having no funds to carry them through so long a period, Evans's agents were induced to remove the engine again, and to set it up in a saw-mill, where it created great astonishment by its extraordinary performance in sawing lumber.

Livingston and Roosevelt were also engaged in experiments quite as early as Fulton, and perhaps earlier.

The prize gained by Fulton was, however, most closely contested by Colonel JOHN STEVENS, of Hoboken, who has been already mentioned in connection with the early history of railroads, and who had been since 1791 engaged in similar experiments. In 1789 he had petitioned the Legislature of the State of New York for a grant similar to that accorded to Livingston, and he then stated that his plans were complete, and on paper.

In 1804, while Fulton was in Europe, Stevens had completed a steamboat, 68 feet long and of 14 feet beam, which combined novelties and merits of design in a manner that exhibited the best possible evidence of remarkable inventive talent, as well as of the most perfect appreciation of the nature of the problem which he had proposed to himself to solve. Its boiler (Fig. 83) was of what is now known as the water-tubular variety. It was quite similar to some now

FIG. 88.-Section of Steam-Boiler, 1804.

known as sectional boilers, and contained 100 tubes 2 inches in diameter and 18 inches long, each fastened at one end to a central water-leg and steam-drum, and plugged at the other end. The flames from the furnace passed around and among the tubes, the water being inside them. The engine (Fig. 84) was a direct-acting high-pressure condensing engine, having a 10-inch cylinder, 2 feet stroke of piston, and drove a screw having four blades, and of a form which, even to-day, appears quite good. The whole is a most remarkable piece of early engineering.

A model of this little steamer, built in 1804, is preserved in the lecture-room of the Department of Mechanical Engineering at the Stevens Institute of Technology; and the machinery itself, consisting of the high-pressure "sectional"

[graphic]

FIG. 84.-Engine, Boiler, and Screw-Propellers used by Stevens, 1804.

or "safety" tubular boiler, as it would be called to-day, the high-pressure condensing engine, with rotating valves, and twin screw-propellers, as just described, is given a place of honor in the model-room, or museum, where it contrasts

[graphic][merged small]

singularly with the mechanism contributed to the collection by manufacturers and inventors of our own time. The hub and blade of a single screw, also used with the same machinery, is likewise to be seen there.

Stevens seems to have been the first to fully recognize the importance of the principle involved in the construction of the sectional steam-boiler. His eldest son, John Cox Stevens, was in Great Britain in the year 1805, and, while there, patented another modification of this type of boiler. In his specification, he details both the method of construction and the principles which determine its form. He says that he describes this invention as it was made known to him by his father, and adds:

"From a series of experiments made in France, in 1790, by M. Belamour, under the auspices of the Royal Academy of Sciences, it has been found that, within a certain range, the elasticity of steam is nearly doubled by every addition of temperature equal to 30° of Fahrenheit's thermometer. These experiments were carried no higher than 280°, at which temperature the elasticity of steam was found equal to about four times the pressure of the atmosphere. experiments which have lately been made by myself, the elasticity of steam at the temperature of boiling oil, which has been estimated at about 600°, was found to equal 40 times the pressure of the atmosphere.

By

"To the discovery of this principle or law, which obtains when water assumes a state of vapor, I certainly can lay no claim; but to the application of it, upon certain principles, to the improvement of the steam-engine, I do claim exclusive right.

"It is obvious that, to derive advantage from an application of this principle, it is absolutely necessary that the vessel or vessels for generating steam should have strength sufficient to withstand the great pressure from an increase of elasticity in the steam; but this pressure is increased or diminished in proportion to the capacity of the containing vessel. The principle, then, of this invention consists in forming a boiler by means of a system, or combination of a number of small vessels, instead of using, as in the usual mode, one large one; the relative strength of

the materials of which these vessels are composed increasing in proportion to the diminution of capacity. It will readily occur that there are an infinite variety of possible modes of effecting such combinations; but, from the nature of the case, there are certain limits beyond which it becomes impracticable to carry on improvement. In the boiler I am about to describe, I apprehend that the improvement is carried to the utmost extent of which the principle is capable. Suppose a plate of brass of one foot square, in which a number of holes are perforated; into each of which holes is fixed one end of a copper tube, of about an inch in diameter and two feet long; and the other ends of these tubes inserted in like manner into a similar piece of brass; the tubes, to insure their tightness, to be cas in the plates; these plates are to be inclosed at each end of the pipes by a strong cap of cast-iron or brass, so as to leave a space of an inch or two between the plates or ends of the pipes and the cast-iron cap at each end; the caps at each end are to be fastened by screw-bolts passing through them into the plates; the necessary supply of water is to be injected by means of a forcing-pump into the cap at one end, and through a tube inserted into the cap at the other end the steam is to be conveyed to the cylinder of the steam-engine; the whole is then to be encircled in brick-work or masonry in the usual manner, placed either horizontally or perpendicularly, at option.

"I conceive that the boiler above described embraces the most eligible mode of applying the principle before mentioned, and that it is unnecessary to give descriptions of the variations in form and construction that may be adopted, especially as these forms may be diversified in many different modes."

Boilers of the character of those described in the specification given above were used on the locomotive built by John Stevens in 1824-25, and one of them remains in the collections of the Stevens Institute of Technology.

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