The Locomotive - Lighthouse Survival Blog

i89;i.j Tii i: L()('u.M(n'i VE. 57
in the originally imperfect constniction of the boiler, or in the wretched condition into
which it has been allowed to get by neglect.
"Consiilering the usual view to be false (that is, that if water be l)rouglit in
contact with a rt*d-hot furnace it will be turned into steam so (jiuckly as to cause an
increase in pressure so sudden and so great that the boiler could not withstand it), tlie
experts of the Manchester Association had for a long time been impelled to l)elieve that
feeding a boiler in which the water level was below the crown-sheet, could not do
otherwise than reduce the steam pressure, cooling the furnace also, and preventing its
possible collapse. To decide this point experiments were made on a boiler 27 ft. 9 in. long
and 7 feet in diameter, with the two internal furnaces, each 3 feet in diameter. The boiler
was mailo entirely of iron, the .shell plates and furnace plates being y^ inch thick, and
and the heads ^^ inch. The heads each had four gussets above the furnaces, and the
front head had two gussets below them, and the rear head one. Each of the two feed
valves (which were in front of the boiler) was connected to a feed pipe discharging
directly over one of the furnaces, six inches above its highest point. The feed water
was therefore sprayed upon the furnaces directly over the grates, and not as usual, back
of the bridge-wall. The safety-valves were set at aboiit 25 lbs. ])er .square inch. The
experiments consisted in firing the boiler up, letting the water level go down until the
highest part of the furnace was bare, keeping the fires bright until the dry furnace
became red-hot, and then injecting the cold feed-water. The results of the experiments
led to the conclusion that spraying cold water on a red-hot furnace crown does not cause
rupture, nor deformation of any kind, nor even a sensible increase in steam pressure ;
but that, on the contrary, when the safety-valve was blowing freely, the index-needle of
the pressure gauge immediately began to travel backward.
"In conclusion, it must be said that the development of the spheroidal state in
a steam boiler is a harmless phenomenon, and that, furthermore, in some special cases it
may be the means of instantly diminishing a pressure already too high."
A BOILER explosion is reported from Eischischek in the province of Wilna, Russia.
The boiler of the public baths at that place exploded on January 6th, killing six persons
in.stantly, ana mortally injuring fifteen others. A similar explosion occurred in the
3Iahommedan baths at Baku, Russia, on March 1st, when the place was crowded. More
than 300 women and children fled naked into the streets, and several persons were
scalded to death.
Word comes from Panama that a boiler exploded recently on the steamer Eal-, near
St. Thomas. Two firemen were killed, and two engineers were badly scalded while
trying to save the firemen.
One account of a boiler explosion, recently received at this oflice, says that "the
boiler in the beautiful steam yacht owned by the son of Mr. A. P. Bliss, of Saginaw,
Mich., exploded yesterday while steaming across the bath tub [!]." Probably this was
ii tov vacht.