Steam:
Its Generation and Use

■4« down the external pipes. The same year John M’Curdy, of New York, made a “Duplex Steam Generator,” of “tubes of wrought or cast-iron or other material” arranged in several horizon- tal rows, connected together alternately front and rear by return bends. In 1826, Goldsworthy Gurney made a number of boilers which he used on his steam carriages, consist- ing of a series of small tubes bent into the shape of a U laid edgewise, which connected top and bottom with large horizon- tal pipes. These latter were united by vertical pipes to per- mit of circulation, and also connected to a ver- tical cylinder form- ing the steam and water reservoirs. In 1828, Paul Steen- strup made the first shell boiler with ver- the large flues, sim- ilar to what is known as the “Martin, ” and suggesting the “Galloway.” The first water-tube boiler having fire-tubes within water-tubes was made in 1830, by Sum- mers & Ogle. Horizontal connections at top and bottom, had a series of vertical water-tubes connecting them, through which were fire tubes extending through the horizontal connections, with nuts upon them to bind the parts together and make the joints, suggesting some recent patents. The first person to use inclined, water-tubes connecting water spaces front and rear with a Wilcox, 1856. steam space above, was Stephen Wilcox in 1856, and the first to make such inclined tubes into a sectional form was one Twibill in 1865. He used wrought-iron tubes connected front and rear by intermediate connections with stand pipes, which carried the steam to a horizontal cross-drum at the top, the entrained water being carried back to the rear. Time would fail to tell of Clark, and Perkins, and Moore (English), and McDowell, and Alban’, and Craddock, and the host of others who have tried to make water-tube boilers, and have not made practical successes, because of the difficul- ties of the problem. Why are not water-tube boilers in more gen- Twibill, 1865. era! use, compared with shell boilers ? is asked. Because they require a high class of engineering to make them successful. The plain cylinder is an easy thing to make. It requires little skill to rivet sheets into a cylinder, build a fire under it and call it a boiler; and because it is easy and any one can make such a boiler —because it re- quires no special engineering — they have been made, and are still made, to a very large extent. The water-tube boiler, on the other hand, re- quires much more skill in order to make it suc- cessful. This is proven by the great number of failures in attempts to make water-tube boilers, some of which are referred to in the paper under discussion. The Babcock & Wilcox Water- tube Boiler has grown out of that of Stephen Wilcox, of 1856, so that it may be said to date back to that year, though the first joint patent was eleven years later. Dr. Alban had stated the axiom that “all boilers should be so constructed that their explosion should not be dan- gerous,” and Harrison had put such boil- ers into use, made of cast-iron globes, but the Babcock & Wilcox boiler of 1867 was the first to combine the sectional construction with a free cir- culation of the water in one continuous round. This construction, known all over the world as the Babcock & Wilcox type, is now almost uni- versally acknowledged to be the best possible for safety, economy, and durability. 25