construction of his first boat, Mr. Stevens of Hoboken, already mentioned, was engaged in a like project, and completed a vessel, to be propelled by a steam engine, within a few weeks after the first successful voyage of Fulton. Stevens was likewise completely successful; but the exclusive privilege of navigating the Hudson by steam having been granted to Fulton by an act of Congress, Stevens was compelled to select another theatre for his operations, and he accordingly sent his steam boat by sea to Philadelphia, to navigate the Delaware, thus securing for himself the honour of having made the first sea voyage by steam.

Fulton did not long retain the monopoly of the steam navigation of the Hudson. Fortunately for the progress of steam navigation, the act conferring upon him that privilege was declared unconstitutional; and the navigation of that noble river was thrown open to the spirit and enterprise of American genius. The number of passengers conveyed upon it became enormous beyond all precedent, and inducements of the strongest kind were accordingly held out to the improvement of its navigation. The distance between New York and Albany, ascertained by a late survey to be one hundred and twenty-five geographical miles by water, had been performed by Fulton's boats occasionally in fifteen or sixteen hours, being at the rate of about eight miles an hour, including stoppages. It became a great object to increase the speed of this trip, so that it might at all times of the year be performed between sunrise and sunset. Robert L. Stevens, the son of the person of that name already mentioned, immediately after the abolition of Fulton's monopoly, placed on the river a vessel which had been built for the Delaware, which easily performed the passage in twelve hours, being at the rate of nearly ten and a half geographical miles an hour. By this increase of speed the improved boats so entirely monopolised the day work upon the river, that the former steamers were either converted into steam tugs to draw barges laden with goods, or used for night trips between New York and Albany. In the night trips the saving of one or two hours was immaterial, it being sufficient that the vessel which left the one port at night should reach the

The river Hudson rises near Lake Champlain, the easternmost of the great chain of lakes or inland seas which extend from east to west across the northern boundary of the United States. The river follows nearly a straight course southwards for two hundred and fifty miles, and empties itself into the sea at New York. The influence of the tide is felt as far as Albany, above which the stream begins to contract. Although this river in magnitude and extent is by no means equal to several others which intersect the States, it is nevertheless rendered an object of great interest by reason of the importance and extent of its trade. The produce of the state of New York and that of the banks of the great Lakes Ontario and Erie are transported by it to the capital; and one of the most extensive and populous districts of the United States is supplied with the necessary imports by its waters. A large fleet of vessels is constantly engaged in its navigation; nor is the tardy but picturesque sailing vessel as yet excluded by the more rapid steamers. The current of the Hudson is said to average nearly three miles an hour; but as the ebb and flow of the tide are felt as far as Albany, the passage of the steamers between that place and New York may be regarded as equally affected by currents in both directions, or nearly The passage therefore, whether in ascending or descending the river, is made nearly in the same time.

So.

(231.) The prevalence of smooth water navigation, whether on the surfaces of rivers or in sheltered bays and sounds, has invested the problem of steam navigation in America with conditions so entirely distinct and different from those under which the same problem presents itself to the European engineer, that any comparison of the performance of vessels, whether with regard to speed or the absorption of power in the two cases, must be utterly fallacious. In Europe a steamer is almost invariably a vessel designed to encounter the agitated surface of an open sea, and is accordingly constructed upon principles of suitable strength and stability. It is likewise supplied with rigging and with sails, to be used in aid of the mechanical power, and manned and commanded by experienced seamen; in fact, it is a combination of a nautical and mechanical structure. In America, on the other hand,

with the exception of the vessels which navigate the great northern lakes, the steamers are structures exclusively mechanical, being designed for smooth water. They require no other strength or stability than that which is sufficient to enable them to float and to bear a progressive motion through the water. Their mould is conceived with an exclusive view to speed; they are therefore slender and weak in their build, of great length in proportion to their width, and having a very small draught of water. In fact, they approach in their form to that of a Thames wherry on a very large scale.

The position and form of the machinery is likewise affected by these conditions. Without the necessity of being protected from a rough sea, it is placed on the deck in an elevated position. The cylinders of large diameter and short stroke invariably used in Europe are unknown in America, and the proportions are reversed, a small diameter and stroke of great length being invariably adopted. It is rarely that two engines are used. A single engine, placed in the centre of the deck, with a cylinder from forty to sixty inches' diameter, and from eight to ten foot stroke, drives paddle-wheels from twenty-one to twenty-five feet in diameter, producing from twenty-five to thirty revolutions per minute. The great magnitude of the paddle-wheels and the velocity imparted to them enable them to perform the office of fly-wheels, and to carry the engine round its centres, not however without a perceptible inequality of motion, which gives to the American steamer an effect like that of a row boat advancing by starts with each stroke of the piston. The length of stroke adopted in these engines enables them to apply with great effect the expansive principle, which is almost universally used, the steam being generally cut off at half stroke.

The steamers which navigate the Hudson are vessels of considerable magnitude, splendidly fitted up for the accommodation of passengers; they vary from one hundred and eighty to two hundred and forty feet in length, and from twenty to thirty feet in width of beam. In the following table is given the particulars of nine steamers plying on this river, taken from

the work of Mr. Stevenson, and from the paper of Mr. Renwick, inserted in the last edition of Tredgold:

None of these vessels have either masts or rigging, and consequently never derive any propelling power except from the engines: they are neither manned nor commanded by persons having any knowledge of navigation: the works that are visible above their decks are the beam and framing of the engine, and the chimneys.

The engines used for steamers on the Hudson, and other great rivers and bays on the eastern coast of America, are most commonly condensing engines, but they nevertheless work with steam of very high pressure, being seldom less than twenty-five pounds per square inch, and sometimes as much as fifty. By reference to the preceding table it will be seen, that the velocity of the piston greatly exceeds the limit generally observed in Europe. It is customary in European marine engines to limit the speed of the piston to about two hundred and twenty feet per minute. Even the piston of a locomotive engine does not much exceed the rate of three hundred feet per minute. In the American steamers, however, the pistons commonly move at the rate of from five to six hundred feet per minute, while the circumference of the paddle-wheels are driven at the rate of from twenty to twenty-two miles an hour.

The hulls of these boats are formed with a perfectly flat bottom and perpendicular sides, rounded at the angles, as represented in fig. 135. At the bow, or cutwater, they are

Fig. 135.

made very sharp, and the deck projects to a great distance over the sides. The weight of the machinery is distributed over an extensive surface of the bottom of this feeble structure, by means of a frame-work of substantial carpentry to which it is attached.

At the height of from four to six feet above the water-line is placed the deck, which is a platform, having the shape of a very elongated ellipse. The extremities of its longer axis are supported by the sternpost and the cutwater, and its sides expand in gentle curves on either hand to a considerable distance beyond the limits of the hull; those parts of the deck thus overhanging the water are called the wheel guards.

Beneath the first deck is the saloon, or dining-room, which also, as is usual in European steamers, forms the gentlemen's sleeping-room. It usually extends from end to end of the vessel. The middle of the first deck is occupied by the engine, boilers, furnaces, and chimneys, of which latter there are generally two. Between the chimneys and the stern, above the first deck, is constructed the ladies' cabin, which is covered by the second deck, called the promenade deck. The great length of these boats and the elevation of the cabins render it impossible for a steersman at the stern to see ahead, and they are, consequently, steered from the bow; the wheel placed there communicating with the helm at the stern, by chains or rods carried along the sides of the boat. Until a recent period, the wheel was connected with the stern by ropes, but some fatal accidents, produced by fire,