IQQ BULLETIN 173, U. S. NATIONAL MUSEUM 



ton who built the engines for the Center Square station of the 

 Philadelphia waterworks in 1801, suggested that wooden boilers be 

 used. These are described below. 



High-pressure steam did not come into favor for many years after 

 Trevithick and Evans, and flue boilers were first developed with the 

 object of obtaining the largest heating surface possible with little 

 regard to increasing the strength of the boilers. Many of the early 

 flue boilers were constructed with single flues of large diameter and 

 were not well designed for strength. As pressures were increased it 

 became necessary to give more attention to strength and the realiza- 

 tion that large heating surface with greater strength could be ob- 

 tained with the use of several flues of small diameter was an impor- 

 tant step forward in boiler design. The Lancashire boiler with two 

 parallel internally fired flues was introduced by Sir William Fair- 

 bairn of England in 1844, and following this a number of variations 

 were introduced. The use of strengthening devices such as cross 

 tubes (first used by Paul Steenstrup in 1828), strengthening rings, 

 and corrugated flues have permitted flue boilers to keep pace with the 

 pressure requirements, and at the present time they are working at 

 the highest pressures employed in ordinary steam-engine practice. 



Fire-tube hoilers. — The fire-tube boiler, with many small tubes 

 within which the flame or hot gases from the fire passed through 

 the water in the boiler, was first suggested by Nathan Read, of Salem, 

 Mass., about 1790. Read, a graduate of Harvard College, began ex- 

 periments with steam engines about 1788, with a view to adapting 

 them to road vehicles and boats. In 1789, at Danvers, Mass., he 

 operated a boat propelled by paddle wheels turned by hand to satisfy 

 himself that the steam engine might be applied to propulsion in that 

 manner, and in 1790 and 1791 he filed with Congress and the newly 

 appointed Commissioners of Patents applications describing steam- 

 propelled land vehicles, boats, and improvements in the steam engine 

 and boiler. Under date of August 26, 1791, the first United States 

 patents were issued, including one to Read for his boiler. The pat- 

 ented boiler was a vertical ioate7''-tuhe boiler with an enclosed firebox, 

 but letters of Read relating to the boiler and sketches found among 

 his papers indicate that he intended the use of the same general 

 design of the boiler with either water or fire tubes. With fire tubes 

 the boiler would resemble the typical vertical hoisting engine boiler 

 of today. It is not probable that Read or James Neville, who pat- 

 ented a similar boiler in England in 1826, used a boiler of this type, 

 and the credit for its first use is usually given to M. Sequin, French 

 engineer, who patented a tubular boiler in February 1828 and applied 

 it to two locomotives early in 1829. The type was brought to prac- 

 tical perfection by George Stephenson, who applied it as the boiler 

 of his locomotive Rocket of 1829. It has been the standard locomo- 



