in which these ropes were burnt, and the steersman lost all power to guide the vessel, caused metal rods or chains to be substituted.

(232.) The paddle-wheels universally used in American steam-boats are formed, as if by the combination of two or more common paddle-wheels, placed one outside the other, on the same axle, but so that the paddle boards of each may have Fig. 136.

an intermediate position between those of the adjacent one, as represented in fig. 136.

The spokes, which are bolted to cast-iron flanges, are of wood. These flanges, to which they are so bolted, are keyed upon the paddle shaft. The outer extremities of the spokes are attached to circular bands or hoops of iron, surrounding the wheel; and the paddle boards, which are formed

of hard wood, are bolted to the spokes. The wheels thus constructed, sometimes consist of three, and not unfrequently four, independent circles of paddle boards, placed one beside the other, and so adjusted in their position, that the boards of no two divisions shall correspond.

The great magnitude of the paddle-wheels, and the circumstance of the navigation being carried on, for the most part, in smooth water, have rendered unnecessary, in America, the adoption of any of those expedients for neutralising the effects of the oblique action of the paddles, which have been tried, but hitherto with so little success, in Europe.

(233.) Sea-going steamers are not numerous in America, the chief of them being those which ply between New York and Providence, and between New York and Charleston. These vessels, however, do not resemble the sea-going steamers of Europe as closely as might be expected; and to those who are are accustomed to the latter, the sea-going

steamers of America can hardly be regarded as safe means of transport.

In the following Table is given the dimensions of five of these vessels, all plying between New York and Providence:

The Narragansett, the finest of these vessels, is built of oak, strengthened by diagonal straps or ties of iron, by which her timbers are connected; she is driven by a condensing engine, and has two boilers, exposing about three thousand square feet of surface to the fire. The steam is maintained at a pressure of from twenty to twenty-five lbs. per square inch: the cylinder is horizontal.

The cabins of these sea-boats are of great magnitude, and afford excellent accommodation for passengers, containing generally four hundred berths. In the Massachusetts the chief cabin is one hundred and sixty feet long, twenty-two feet wide, and twelve feet in height, its vast extent being uninterrupted by pillars or any other obstruction. "I have dined," says Mr. Stevenson, "with one hundred and seventyfive persons in this cabin, and, notwithstanding this numerous assembly, the tables, which were arranged in two parallel rows, extending from one end of the cabin to the other, were far from being fully occupied, the attendance was good, and every thing was conducted with perfect regularity and order. There are one hundred and twelve fixed berths ranged round this cabin, and one hundred temporary berths can be erected in the middle of the floor: besides these there are sixty fixed berths in the ladies' cabin, and several temporary sleep

Part of strokeatwhich

stroke is cut off.

ing places can be erected in it also. The cabin of the Massachusetts is by no means the largest in the United States. Some steamers have cabins upwards of one hundred and seventy-five feet in length. Those large saloons are lighted by Argand lamps, suspended from the ceiling, and their appearance, when brilliantly lighted up and filled with company, is very remarkable. The passengers generally arrange themselves in parties at the numerous small tables into which the large tables are converted after dinner, and engage in different amusements. The scene resembles much more the coffee-room of some great hotel than the cabin of a floating vessel."

(234.) Nothing has excited more surprise among engineers and others interested in steam navigation in Europe, than the statements which have been so generally and so confidently made of the speed attained by American steamers. This astonishment is due to several causes, the chief of which is the omission of all notice of the great difference between the structure and operation of the American steamers and the nature of the navigation in which they are engaged, compared with the structure and operation of, and the navigation in which European steamers are employed: as well might the performance of a Thames wherry, or one of the fly-boats on the northern canals, be compared with that of the Great Western, or the British Queen. The statements alluded to all have reference to steamers navigating the Hudson between New York and Albany, the form and structure of which we have already described; and doubtless the greatest speed ever attained on the surface of water has been exhibited in the passages of these vessels.

Mr. Stevenson states, that exclusive of the time lost in stoppages, the voyage between New York and Albany is usually made in ten hours. Dr. Renwick, however, who has probably more extensive opportunities of observation, states, that the average time, exclusive of stoppages, is ten hours and a half. The distance being 125.18 geographical miles, the average rate would therefore be 11 miles per hour. If it be observed that the average rate of some of the best sea-going steamers in Europe obtained from experiments

and observations made by myself, more than three years ago, showed a rate of steaming little less than ten geographical miles per hour, and that since that time considerable improvements in steam navigation have been made, and further, that these performances were made under exposure to all the disadvantages of an open sea, the difference between them and the performance of the American river steamers will cease to create astonishment.

Dr. Renwick states that he made, in a boat called the "New Philadelphia," one of the most remarkable passages ever performed. He left New York at five in the afternoon, with the first of the flood, and landed at Catskill, distant 95.8 geographical miles from New York, at a quarter before twelve. Passengers were landed and taken in at seven intermediate points: the rate, including stoppages, was therefore 14.2 miles per hour; and if half an hour be allowed for stoppages, the actual average rate of motion would be fifteen miles and three quarters an hour. As the current, which in this case was with the course of the vessel, did not exceed three miles and a half an hour, the absolute velocity through the water would have been somewhat under twelve miles an hour. This speed is nearly the same as the speed obtained from taking the average time of the voyages between New York and Albany at ten hours and a half; it would therefore appear that the great speed attained in this trip must have been chiefly, if not altogether, owing to the effect of the current.

(235.) The steamers which navigate the great northern lakes differ so little in their construction and appearance from the European steam-boats, that it will not be necessary here to devote any considerable space to an account of them.

These vessels were introduced on the lakes at about the same time that steamers were first introduced on the Clyde. These steamers are strongly built vessels, supplied with sails and rigging, and propelled by powerful engines. The largest in 1837, when Mr. Stevenson visited the States, was the James Madison. This vessel was one hundred and eighty-one feet in length on the deck, thirty feet in breadth of beam, and twelve feet six inches in depth of hold: her draught of water was ten feet, and her measured capacity seven hundred

tons.

She plyed between Buffalo on Lake Erie and Chicago on Lake Michigan, a distance of nine hundred and fifty miles.

The severe storms and formidable sea encountered on the lakes render necessary for the navigation, vessels in all respects as strong and powerful as those which navigate the

open ocean.

(236.) By far the most remarkable and important of all the American rivers is the Mississippi and its tributaries. That part of the American continent which extends from the southern shores of the great northern lakes to the northern shores of the Gulf of Mexico, is watered by these great streams. The main stream of the Mississippi has its fountains in the tract of country lying north of the Illinois and east of Lake Michigan, in latitude forty-three degrees. At about latitude thirtynine degrees, a little north of St. Louis, it receives the waters of the Missouri, and further south, at the latitude of thirtyseven degrees, the Ohio flows into it, after traversing five degrees of longitude and four of latitude, and winding its way from the Alleghany range through several of the states, and forming a navigable communication with numerous important towns of the Union, among which may be mentioned Pittsburg, Cincinnati, Frankfort, Lexington, and Louisville. The main stream of the Mississippi, after receiving the waters of the Arkansas, and numerous other minor tributaries, flows into the Gulf of Mexico by four mouths. The main stream of the Mississippi, independently of its tributaries, forms an unbroken course of inland navigation for a distance of nearly two thousand three hundred miles. Its width, through a distance of one thousand one hundred miles from its mouth, is not less than half a mile, and its average depth a hundred feet. The Ohio, its chief eastern tributary, flowing into it at a distance of about a thousand miles from its mouth, traverses also about the same extent of country, and is navigable throughout the whole of that extent. This river also has several navigable tributaries of considerable extent, among which may be mentioned the Muskingum, navigable for one hundred and twenty miles; the Miami, navigable for seventyfive miles; the Scioto, navigable for one hundred and twenty