144 Notice of the Revolving Steam Engine. 



dark glass from the telescope and I had to contend with al- 

 ternations of partial observation and intense light. 



From the above observation, by a cursory calculation for 

 the accuracy of which I cannot fully vouch, I make the lon- 

 gitude of the Cupola of Columbia College 74.° 5.' 11." or 

 in time 4hrs. 56.' 23." 4 W. from Greenwich. The mean 

 of a number of Chronometers makes it about 74.° 8.' W. 

 and the Longitude given upon Eddy's Map is 74.° 0.' 

 45." W. I am Sir, 



Your most obedient Servt. 



JAS. RENWICK. 



Art. XX. — JSoiice of the Revolving Steam Engine ; by 

 J. L. Sullivan, Esq. 



Columbia, S. C. March 1, 1822. 



J[Ir. Silliman — Sir, 



Had I no other motive to offer you a further communi- 

 cation on Moreyh Steam Engine, I should think it due to 

 your Journal, in which an account of this form of the ma- 

 chine had been given to the public at an early period, to 

 state the fact of its successful employment ; but I find a 

 farther reason for doing so in the opinion expressed by 

 Ward in your 4th volume, while describing his invention. 

 He* fears that Morey's engine will not be durable, because, 

 as he thinks, the friction between the parallel guides and 

 the brasses that move on them, will be such, as to affect 

 the parallelism of the pi3ton-rod. This was to assume, 

 that it would be impracticable to apply any anti friction sub- 

 stance to this part cf the machine. Bkit in practice, nothing 

 was easier than to attach to each side an oil-box, with a few 

 small holes in the top thereof, covered with a sponge, which 

 as the engine revolves imbibes the oil, while the brass at 

 each stroke reaches, and a little compresses this sponge, so 

 that the steel guide pieces, are continually lubricated. And 

 thus far it h?,s performed satisfactorily, ascending the Santee 

 and Congaree, towing heavy loads against a strong current. 

 We call the steam boat, in which this engine operates the pat- 

 ent, in allusion to her claim, or right to navigate the waters of 

 New-York, notwithstanding the monopoly granted by the 



