8 Account of Steam-boats 



sion of the parallel motion. The upper end of the piston-rod 

 bears a cross bar, which works between guides formed of iron 

 plates, screwed down upon upright posts. If nothing be gained 

 in the working of the engine, much is in the fitting it up; 

 for the parallel motion, of all parts of the engine, requires per- 

 haps the most accurate workmanship. 



The external appearance of the engines of the North Ame- 

 rica is less finished than the better class of English engines. 

 There is, however, no real inferiority. The castings, made at 

 the Westpoint foundery, are excellent ; the boring of the cylinder 

 and air-pump is perfect, and the fitting up. performed under the 

 immediate direction of Mr. Robert L. Stevens, is not to be ex- 

 ceeded. I mention this, because the only specimen of an 

 American steam-boat that has yet reached Europe, was most 

 deficient in all these particulars. That vessel was, however, 

 in every respect, far behind the better class of our steam- 

 boats, even at that distant period (1816), and vastly inferior 

 to those which are now constructed. 



In our boats intended for the navigation of rivers, several 

 points necessary to be observed in those intended for the ocean, 

 may be omitted. It is, for instance, unnecessary that the 

 engine should work under deck. Hence in all our engines the 

 length of the stroke is greater than those described to me in the 

 English steam-boats ; in the latter, also, the position of boilers, 

 and even of the engine, upon the wheel-guards, would be im- 

 proper, and thus much of the comfort, that this plan affords to 

 the passengers in the North America, would be unattainable. 

 As the steam-boats on the Hudson never make use of sails, 

 and as the waves rarely run high, every other property of a 

 vessel for navigating the ocean, except stability (for instance, 

 the capability of holding close to the wind), may be neglected, 

 in the search for the prow of least resistance. 



In the steam-boats on Fulton's plan the engine varies 

 from those of Watt, and consequently from those of Ste- 

 vens, in the suppression of the working beam ; the reciprocat- 

 ing rectilineal motion of the piston-rod is changed into circu- 

 lar by means of two connecting rods, attached to a cross bar 

 upon the top of the piston-rod ; these take hold of cranks, or 



