92 IMPROVEMENTS IN STEAM ENGINES. 



the intended purpose. He has made other improvements in 

 the construction of steam-engines, of which I shall also give 

 you some account. Nor ought I to omit the mention of a small 

 engine, erected by Mr. Oliver Evans, as an experiment, with 

 which he grinds Plaister of Paris, nor of the steam-wheel of 

 Air. Briggs. 



1st. The Manhattan company's engine at New- York, is up- 

 on the principle of Bolton and Watt's double engines, without 

 any variation. It has two boilers; one a wooden one, upon 

 the construction of those first put up in Philadelphia, the 

 other of sheet iron, on Bolton & Watt's construction. The 

 ily-wheel is driven by a sun and planet motion,, and the shaft 

 works three small pumps with common cranks. 



2d. Mr. Roosewelt's engine has all the improvements which 

 have been made by the joint ingenuity of Messrs. Smallman & 

 Staudiiiger, with the assistance of the capital and intelligence of 

 Mr. Roosewelt; and which have also been adopted to the 

 engines, belonging to the water-works at Philadelphia. 



3d. The engines at Philadelphia, independently of these 

 improvements, act also upon a pump, the principal of which, 

 though not new, has never before, I believe, been used upon 

 a large scale; and which is worthy of being particularly de- 

 scribed. 



I shall now proceed to describe these innovations, for expe- 

 rience does not permit me as yet to call them all improvemeyits, 

 although I have no doubt, but that they will furnish hints 

 of use to bring the steam-engine to greater perfection. 



1st. THE WOODEN ROILER. 



Wooden boilers have been applied in America to the pur- 

 pose of distilling for many years. Mr. Anderson, whose im- 

 provements in that art are well known, appears to have first 

 introduced them in America. But it was found that the mash 

 had a very injurious effect upon the solidity of the wood : for 

 while the outside retained the appearance of soundness, and 

 the inside that of a burnt, but hard surface, the body of the 

 plank was entirely decayed. It was however still to be tried,. 



