Morning journal and courier., 1881-06-21
Tuesday Mornlng, June 21. 1881.
WHY DO ROLLERS EXPLODE:

WHY DO BOILERS EXPLODE:
 There are many theories concerning the causes of boiler explosions and many experi- ments have been made to test them. A few years ago United States government com mission made some interesting experiments of this nature near Pittsburg, Pennsylvania, but did not succeed in producing genuine boiler explosion. MT. D. T. Lawson has lately been experimenting at the same place, and has, it is stated, succeeded in doing what the government commission did not do.
 MT. Lawson had boiler made of the very best iron, which showed a tensile strength of 624 pounds to the square inch, according to the United States standard It was six feet in length and thirty inches in diameter. The cylinder of an old steamboat engine was ccn- nected with the boiler by means of a two inch pipe, in which was fitted quick lifting valve. The steam was permitted, by means of this valve, to enter the cylinder in the same manner as 1t enters the cylinder of any ordinary engine with the exception that it was not cut off suddenly, as in working en- zine. Had it been, MT. Lawson claims, the explosion would have been still more certain.
 
 the furnace was fed with petroleum by means of a small pipe connected with tank located at safe distance. The final test was made at pressure of 380 pounds, 8 little over half the capacity of the boiler At this time the water was eight inches above the fire ine, the boiler being at least three-fourths full. The valve was lifted quickly, and no sooner was the cylinder filled with the rush ing steam than a slight shock was felt, fol- lowed by terrific report. Vast volumes of steam enveloped everything but there were no signs of any hot water, it all having burst into steam when the pressure was removed. The report had scarcely died away before a shower of condensed steam began falling, ac- companied by pieces of iron. bricks, steam pipes and other debris. Scarcely 8 vestige of the furnace or boiler was left The latter had not merely given way at single point, but was literally torn into fragments. One of the largest pieces found was about foot and half long and foot wide It had been blown fully half mile. One of the heads was found nearly half mile from the bombproof.
 MT. Lawson claims that the only explosive element in 8 steam boiler is superheated wa ter; that water, highly superheated, ex- plodes by sudden reduction of the pressure from it's surface. When the water is super heated the engineer opens the cylinder port, and instantly the steam fills the cylinder creating vacuum to that extent over the su- perheated water in the boiler, a portion of which bursts into steam to restore the re-
 
 square inch of the boiler with concussive force many fold greater than the regular pressure of the steam, and consequently nu merous explosions occur just as steam is turned into the cy1ind at starting, and be- fore it's passage from the boiler has become unifmn. Another prolific source of explo- sion5Mr. Lawson claims is the sudden con- densation of steam over the superheated wa ter in the boiler, thereby creating 8 vacuum and consequent removal of pressure, when 1 the water bursts into steam with a | concussive force that is generally irresistible.
 This is plausible, and the success of Mir. | Lawsons experiment gives support to his theory He has invented boiler in which l he claims that the pressure is kept approxi 1 mately uniform on the surface of the super heated water. thus preventing the dangerous 1 effect which must follow the sudden reduc l tion of pressure from it's surface.