National Republican., 1881-01-07

Tests inspections and trial of steam boilers" is
chapter which again has grave interest outside OF
eeeaev a test lie Gm no e hnn propey T IS
almost always dependent The difficulties in the
way of thorough test are often very great There
is, therefore, grave significance in the authors
words:
Boilers which are faulty in design or built of
inferior material, or have had workmanship put
the varying and continued strains of actual prae-
uce they VIII sooner or Later develop weaknesses
which seriously impair their life and safety. Grave
defects may be hidden from view after boiler is
built so that they cannot be discovered by the
closest scrunity. Therefore, the inspection OF
boilers should commence with the process of con-
struction and should repeated frequently during
the lifetime of the boiler"
The tricks resorted to by boiler makers, such as
punching the rivet holes too close to the edge OF
the plates when these happen TO be cut too small
are here pointed out. The various kinds of tests
and their relative values are minutely examined
Management of Boilers" takes the engineer skill
and leads naturally to the consideration OF
Causes and prevention ofthe deterioration OF boil
ers" In general the deterioration arises from the
accumulation of scale or sediment, from corroson,
fracture burning or distortion of plates. These
generally traceable to defects of design MATERIAL or
workmanship; to mismanagement, the use Of sui
phurouS fuel or impure water and to galyanle ac-
lion. In addition to this formidable catalogue the
author says: "There are some destructive agencies
at work shortening the life Of boilers the action of
which is not fully understood; and instances OF
the rapid deterioration of boilers occur from time
TO time for which no definite cause can be as
signed" Stationary boilers frequently last twenty
years the life of marine boilers ranges, under fav-
orable conditions, from nine to twelve years, and
in naval vessels is often limited to six years of use
The varying conditions of prolonged strain and
prOtracted idlenesS of frequent impOSSibiity, dur
ing long cruises on distant stations, of regular
cleaning and repairs, account for the shorter life
of the war steamers boiler. The closing chapter
is devoted to subject ugly in ITSELF but is
of the means by which the life of the boiler is de-
termined, must have place-namely, Boiler Ex-
ploSions:"
tanee that the true causes OF every boiler explO-
sion should be clearly understood in order that
their recurrence may be guarded against. The
tendency to ascribe explosions TO obscure causes,
rather than toregard them the natural results
of conditions which can be prevented by inteli-
gent care exercised lnthe design construction, and
management of boilers, has, nc doubt, its origin
in the desire TO escape responsibility for the
suits of culpable neglect and has been productive
of much mischief by engenderIng careleSsneSs on
the part of owners ana attendants OF steam DOLL
erS."
1t is not sufficient to show that q certain set of
circumstances could exist In a case OF explosion,
but that they actually qld exist Severa OF the e&
trayagant theories such as sudden deYelOpmentOf
electricity the formation ana detonatlon OF nydro-
gen and oxygen, the constituent gases OF water,
the instantaneous conversion into steam OF large
masses of water and so on, are satisfactorily met
and disposed of Apart from external injury or
violent conclusion the explosions OF boilers are
generally tr@eeabe to unaeaeG,ed or OF ,on %n
ance or caselessnesS of management either
in the boiler itself or the furnace chamber and
fuel supply We cannot follow this part of the
subject further, but it has vital interest that
recommends il TO reconsideration OF every person
concerned i'll the ownership and management OF
boilers. We have, indeed. barely skinned the
work in giving our testimony 10 Its great value
and the labor and knowledge it represents. These
only be estimated by reading 1t carefully from
cover to cover and knowing how Tar 1t distances
any work of the kind which pre;ends to give IN
formation the subject up to the requirements Of
the present day.-Nclu York Herald,