The New York herald., 1873-11-20
OUR NAVAL THUNDER.
The Efficiency of Our System OF
Marine Armament.
THE RESULTS OF EXPERIMENTS
Official Tests of Powder, Cartridges, Calling
Guns and Artillery.


The Chief OF the Bureau OF Ordnance has sub
mitted mis- annual report to the Secretary OF the
Navy concerning the operations OF his depart
ment for the past IL months. 1t is, perhaps, to be
regretted that many questions relating to the
equipment and armament OF our ships are not
mentioned in this document But it was written
some time previous to the occurrence oil the recent
atrocities at Santiago de Cuba, which have sud
denly aroused public attention to the condition OF
our navy.
There are, however, some points In the report
which are OF interest. Although the appropria
tions for experimental purposes were so far lin
tted as to prevent him from making full
Investigation OF many new devices and
theories which have been either orgi
mated in this country or brought TO public
attention abroad, the Chief OF the Bureau has not
been unmlndful OF the important questions con-
nected with the armament OF ships, nor OF new
means OF offence and defence, IN order that we
may keep pace with the work of other nations.
large amount OF information has been collected
and arranged for future reference; while during
the year, and within the scope OF the expenditure
allowed by Congress, much has been done in the
Tay Of preliminary inquiry.
The small battery near Annapolis is gradually
being brought into working order, and during the
next season will be in readiness for efficient
best apparatus for observing ranges and velocties,
and 1t can also afford heavy practice against armor
plating when required.
The solution OF the powder question in re-
epect to the relation OF velocities to pressures.
nrst prominently brought forward by General Rod
man, remains the most important and, therefore,
receives special attention. 1t Is one in which
theories are of no avail; experiment alone can
determne the qualities required in different guns,
and the most satisfactory results have been OBJ
1ained in this direction.
While seeking to obtain the highest velocity due
TO given charge of powder care must be taken
TO reduce to a safe limit the rupturing force, and
10 make 1t uniform in its action. To this end
series Of experiments in the manufacture OF
powder, particularly the large grained for heavy
cannon. was instituted by his pI edecessor (Rear
Admiral CaseJ, at the Annapolis battery, in con-
junction with the mills of the Messrs Dupont near
Tar In producing powder which gives with sub
stantal uniformity In the 10 inch gun velocity OF
1.S00 eet, with pressure OF not more than 10000
pounds per square inch upon the bore OF the gun.
This improvement upon the old manufactures may
oe understood rom the TACT that the samples OF
unfortunately from 1000. fired July s. 1872 gave
I'm charges OF 100 pounds) Irregular velocties and
pounds 800 feet and 81, 500 POUNDS; 5O4 feet and
IS, 500 pounds, &c.
The effect OF such variable propelling forces and
may be readily imagined.
THEY ARE EXTREMELY PREJUDIcIAL
to guns OF any kind. but peculiarly dangerous TO
the cast iron ordnance OF our navy. Wherefore ii
may be said that their safety is insured proper
ti0nately to the uniformity attained In the
tl0n OF the powder used in them, the object being
high vel0citles and low pressures.
The best results obtained with grains or
definite form, regular surfaces and Uniform
density. simple method OF securing these essen
tlal points. proposed by the Chief OF the Bureau,
has been adopted Charges of loo pounds, made
up OF these hexagonal grams, were fired from 15-
Inch smooth bore gun on the 10th OF August, 1872.
They gave
vELoCITIES AND PRESSUREs,
respectively, OF 643 feet IS 500 pounds, 635 feet
and So 500 pounds and 1611 feet 80 900 pounds Ii
seems that the officers OF the other branch OF the
ordnance service are fully alive TO the necessity for
Improvement In this direction, FOR Commodore
gefers adds that sin the solution OF this important
question friendly rivalry Is maintained by the
army authorities, an example OF which is shown Ia
the following extract from an Official report just
made and kindly sent to me by the Chief Of Ord
nance. In this instance a 12-lnch cast iron rine
WAS used In firing the heXaponai grains