Steam:
Its Generation and Use

This fact was disclosed to some of the officials of the prison, and an investigation was instituted to ascertain the cause, disclosing a fact that at once relieved the boiler from any responsibility for the absence of steam—for there was no water in it. It also showed that the blow-cock was wide open, and had been since the night before. What followed, we give in Mr. Watson’s own words: “After the syndicate had opened the furnace door and seen the white hot tubes, it was thought a good idea to get some water in the boiler as quickly as possible ; so they shut the blow-cock and turned on the city water. The result justi- fied their expectations; steam was made very quickly; for a moment it roared through the safety valve with a fearsome sound ; and that is all that happened, beyond the renewal of a few of the tubes, and one steel casting.” What might have happened had either of these boilers been fire-tube instead of water-tube boil- ers, we do not pretend to say, but think Mr. Watson is not far out of the way in venturing the statement that “ it is not contrary to precedent to say that, in all probability, there would have been an opportunity for a coroner’s inquest and a new jail.” Caution Necessary. It must not be assumed, however, that the mere presence of water tubes in a boiler will make it safe. On the contrary they may be com- bined with other features exceedingly dangerous, such as flat surfaces, stayed or unstayed, as in the “Phleger” boiler, which exploded in Phila- delphia some years ago, and the “Firminich” boiler which exploded in St. Louis, Oct. 3d, 1887. A number of porcupine boilers have also been put forth as “safe” because of their water tubes, though the large central shell is made like per- forated card-board, by the numerous holes. To make the matter worse, expanding the tubes into these holes seriously strains the metal, mak- ing a weak construction weaker still. That a boiler can be made so as to be practi- cally safe from explosion is a demonstrated fact of which no one at all acquainted with modern engineering has any doubt. Of this class of boil- ers the Babcock & Wilcox is a preeminent ex- ample, from the length of time which it has been upon the market, the large number which have been for years in use under all sorts of circum- stances and conditions and under all kinds of management, without a single instance of disas- trous explosion. The Babcock & Wilcox water-tube boiler has all the elements of safety, in connection with its other characteristics of economy, durability, accessibility, etc. Being composed of wrought iron tubes, and a drum of comparatively small diameter, it has a great excess of strength over any pressure which it is desirable to use. As the rapid circulation of the water insures equal tem- perature in all parts, the strains due to un- equal expansion cannot occur to deteriorate its strength. The construction of the boiler, more- over, is such that, should unequal expansion occur under extraordinary circumstances, no objectionable strain can be caused thereby, ample elasticity being provided for that purpose in the method of construction. In this boiler, so powerful is the circulation that as long as there is sufficient water to about half fill the tubes, a rapid current flows through the whole boiler; but if the tubes should finally get almost empty, the circulation theil ceases and the boiler might burn and give out; by that time, however, it is so nearly empty as to be incapable of harm if ruptured. Its successful record of over twenty years proves that by the application of correct princi- ples, the use of proper care and good material in construction, a boiler can be made so as to be in fact as well as in name a “safety boiler.” Return Tubular Boiler at the Edison Electric Light Co.’s Works, West Chester, Pa. Exploded Decern lier 17, 1887, killing seven and wounding eight people. 13