Year: 1860

-,-,.,, ~ s,.,,, F,o,lers Causes-Nhat Is Steam.


The late explosions of steam boilers attached to the
distery of Furman Foley, in Williamsburg on the
ID inst and that of Ames 4 Moulton hat acCory new
York on the Sd inst and that of recent occurrence at
Wilmington N. O., has attracted the attention OF many
nersons and engineers familiar with the general causes
and results These explosions are becoming everyday
with results altogether too disastrous TO De
quietly acquesced in The uncertainty OF the Gauss o
these explosions seems to nave rendered all Sale't
valve - inventions of little USE


Explosions are attributed by many to electricity IN
asmuch as steam is known to be an electrc generator
Scientific men, however, assert that steam when cor
fined in state of rest is not electric, Out only wheh IN
motion and argue that therefore explosions cannot be
caused by electricity. Let first go into detals ana
examine correctly what is steam. Using extracts from
letter by Mr. John Fl. Loper, Engineer, late OF the
United States Navy Yard at Gosport Va 1t reason,
able to conclude that steam is electric ud generated
from water by the application of heat arising at the
boiling point of 2l2 degrees the pressure OF which IS
equal to that of one atmosphere namely l4M pounds
Der square inch Vapor is formed only from the sur
face steam from the body of the liquid Evaporatlcn
proceeds at all temperatures steam only formed when
the fluid has arrived at certain liked temperature
The formation of steam is violent process the torma-
tion of vapor gradual and nsensibe Steam 1t be not
heated after the separation has taken place. is called com
steam Steam in separate vessel or even allow not
air or fame to in contact with the steam chest,
will become hotter without absorbing fresh particles
among its general mass and is called "super-heated
steam" Steam which has an excess OF Watery Vapor,
is called surcharged steam. Steam which Is on the
point of condensation, and will condense (partlay at
least on the slightest dminuou of pressure or eXpan-
sion of volume is called saturated steam. One thou
sand degrees of heat are absorbed in the conversion OF
water into steam this is called its " latent heat
Every engineer is well aware that when steam from the
upper cock has blue appearance there is danger but
every does not know that this blue appearance lnd-
cats hydrogen gas, and IN state OF lntammaDy. 1he


flame of this gas is light blue and only burns when in
contact supplied with oxygen Owing to its being the
hghest of all gases it rises to the upper part OF the steam
jacket in the boiler where pipe could be introduced and
conducted to the engineers room The engineer could
occasionally try the cock and ascertain the formation
of hydrogen in the boiler from the Color and through
this pipe allow it to escape and steam would then take
its place in the boiler. The question now arises, how
the decomposition OF water In steam boilers and the
formation OF hydrogen be prevented and remedy ap-
piled by which boilers will not explode? Mr.. LOper
clearly states, his opinion, that nearly all boilers thus
charged explode opening the " satetyvalve = the
steam rushes out in conica torm the base OF the cone
uppermost thus leaving space in the centre through
which the crcumambient atmosphere rushes, supplying
of course, oxygen


If then the water is low in the boiler the steam de-
composed and hydrogen gas the lghtest and most
plcsive, rapidly formed the supply OF oxygen of which
is only necessary to combine with it one third to
produce of the most terrific explosions, the effect Of
which will be far greater than gun powder OF the strong
| est detonatiHg compounds


Therefore, in no case should the engineer open his
saeyvave until he has tried the upper cock the bo
Ter and should the blue appearance of the steam lnd
cate hydrogen, he should keep his safety shut and
work off the hydrogen through the cylinder. The wr


ter, in concluding his letter. dwels this of the
most important of boiler explosions. Using high
or low steam also, too great amount of steam or
pressure boiler defective in its strength and
mends that all high pressure boilers should be subjected
to the trial OF the hydostac pressure of the United
States Inspector of to safety and that
the qualifications of the engineers attending the same
should be known by the class of their Engineers Ger


fcate given them by the Inspector according to their
examination, is required of steamboat engineers By
doing, the Act of Congress approved August 3Oh,
1882, Section II, would be carried fully into effect and
better security given to the lives of all persons interest
ed