Washington sentinel., 1854-05-07
From the Washington Union Of April g.
Prevention Of Steam-bofIer Explosions.

The country is so frequently startled and
saddened by the terrible havoc Of life made by
explosions of steam-b boilers on our nayigable
streams, that an efectual preventive against
such catastrophes has long been desderatum.
An improvement in the steam boiler has lately
been made which claims to be an .effectual
remedy against the recurrence of these calami-
ties. Upon application by the inventor to the
Secretary of. the Navy, that officer promptly
granted the privilege Of subjecting the inven-
ton to thorough trial at the navy yard The
test was made on Friday last, and we learn that
it was highly satisfactory. Not being able to
be present, we procured gentleman of large
experience and practical skill in such matters,
to attend and furnish US with the result and
such description ofthe improvement as would
give to our readers an Ineligible idea of so
valuable an invention. He has kindly furnished
us the following:
REEDER's SAFETY-GUABD.--We vores amply
paid yesterday, in our visit to the navy yard, in
witnessing the practical operations of this
safety-guard or rather fire annihilator, for the
prevention Of the explosion Of steam boilers
from excessive pressure. Its simplicity, as well
as accuracy, beside the steam-gauge, cannot
fail to attract the most casual observer From
the operator, Captain Harrison, we learn there
is guard of this order on the stea aler William
Garvin, high-pressure boat plying between
Louisville and Nashville, which, fully meets all
the ends desired. Those skilled in such mat.
ters, without hesitancy, give it high endorse
ment So far as we are judges, it involves no
new principles, but adheres strictly, in its CON
struction, to well-established rules that have
been long settled as accurate. They are, how
ever, simpli6ed and brought to level with the
uneducated yet practical mechanic.
The original feature, we observed, was its
simplication, and the idea of drawing toater in
stead of steam from the boilers, to suppress that
hitherto unruly vapor. This operation is per-
formed by process similar to the one of long
use in the soda fount, namely: the insertion Of
q tube through the gas into the water, which,
by pressure, forces up the tube such quantities
of water as may be desired, with certainty and
velocity. This guard is similarly tubed, so as
to receive water from the boilers instead of
steam, which it passes beyond, reaching water,
which is forced up the tube by the pressure of
steam above it, till it comes in contact with an
ordinary valve, which rises from its seat, forces
its way into cylinder placed immediately on
top of the boiler, which has capacity sufficient
to contain water, as well as encase the entire
working part of the guard; so that, whilst steam
is up, it is placed beyond the reach of inter-
meddling or additional weighing; therefore,
the slightest pressure above the maximum set
in the valve for safety will cause it to rise and
fill the cylinder with water. After the water
reaches the cylinder, it is conducted therefrom
by an opening in its bottom to suitable lead
ing pipe, from thence to waste pipes, running
from the leadpipe, and directly over the entire
fire surface thus is enabled, without the inter
ference or attention of man, to entirely or par
tally extinguish the fires, and so control that
element when inclined to excess, which is the
cause of attaining excessive pressure, and that
at the cost of vast sacrifice of human life and
property.
The ordinary ysafetyvalve has heretofore been,
| and is now by many deemed all.suficient to
guard against pressure, properly used; but time
and experience teach the reverse-that the
remedy is not always sovereign. It has been,
and is yet, liable to be tampered with, and all
traces oftampering instantaneously removed by
those under whose control it is placed; there
fore, liable as it is, and whilst mankind is con.
stituted ignorant, reckless, or inattentive, it
cannot be sovereign. True, we may say it will
raise given pressure if unmolested; yet it
cannot be denied that it is out of proportion
when relied upon to selfact; that the area of
inches for escapement, when considered with
the area of surface on series Of boilers--tha
the first bears no proportion to the latter.
Hence, although it may escape steam, it only
partially relieves, inasmuch as the boiler sur
face being the greater, consequently steam
must accumulate with more rapidity than it is
discharged: to increase the opening Of the
valve-seat to proper proportion is impracti-
cable for ordinary use. This is the case, and
is susceptible of a mathematical proof if fig
ures are tedious and beyond the capacity Of
the ordinary practical engineer, let him make
a comparison with high head of steam, sufi-
cient to raise the valve, with fierce fire, and
the result will be that, Notwithstanding the
valve is doing as much as its capacity will ad-
NIT by way of a discharge, yet comparison
between the valve and steam gauge the latter
being the better criterion to Judge from, will
show an excess of pressure over the valve Of
25 or 80 pounds.
Now, to account for this seeming inaccuracy,
it is rational to conclude this excess must pro-
ceed from rapidlyaccumulate steam, from
fermentation or surcharge. Experience teaches
that thus accumulated, excessive pressure can
produced overwise than by intermeddling with
the valve by additional weighing; but, un-
fortunately, we, without reflection, instead of
giving our opinion upon the causes which pro-
duce the difference between the two tests, turn
it over wholesale upon the engineers, accuse
them of overwhelming the valve. This is
natural; for ninety nine out Of hundred have
taken the theory of the safety-valve on faith,
without examination on their part Now, so far
as Reeder's guard is concerned, its introduction
does not propose to do away with the ordinary
safty-valve now in use, Imperfect as it ISL
desires it as partial auxiliary, and, when tam {.
pered with, or it fails instantly to discharge the
dangerous excessive accumulated pressure be-
yond the moment of safety, to step in, arrest the
cause, fire, and effectually prevent further
accumulation of steam. Reeder's saftey-guard
is, therefore, so constructed with little or no
show to prevent its action. True when in the
absence of steam, the tube from the boiler
might he stopped at the bottom; yet it would
be done coolly, with deliberation; detection
would follow, and the severest penalties of the
law would be meted to the perpetrator.
Now it seldom happens (if every that an en-
gineer perpetrates wrong, or runs a risk,
when calm and at himself 1t happens under
undue excitement generally. with excitement,
ambition, and steam up; them ND then it is,
that racing takes place; reason becomes de-