New-York tribune. [volume] (New York [N.Y.]) 1866-1924, 1880-01-30

be impregnable to anything yet devised for a.'a'n
by water approach. The end of the Rebellion lou"u
the Ordnance Office in the possession OF large nun
Der of cast-iron smooth-bo muzzle-oading hoo
man guns which experience had proved 70 20
among the best, if not the very best' smoo'n-ooi0
large ouns made There were about 1 800 OF THESE
guns in store. of which number three-quarers were
ten-inch and the remainder ffteen-nch guns. III
their present condition these guns are OF 10 uso
but by outstanding the meagre appropriation anu
extending over several years series OF experiments
which might have been completed in single season,
American ordnance officers have demonstrated that
the ten-nch Rodman smooth-bores can DC CONVERGE
into eight-inch rined guns which will be equal in
every respect To the best guns of the same caiDre
and length manufactured elsewhere. The cohVei-
sion Is accomplished by inserting in the smooth-
bore a riied lining of wrought-iron one inch III
thickness. work requiring the application Oh tne
highest scientific and mechanical skill.
The work of experiment, in so far as the cohVer-
sion OF smooth-bore ten-inch guns into eight-ihcn
rifles is complete and about 125 such guns nave
already beea placed in position on the coast iorli
cations Three four of these guns have peeh
fred about 500 times each, and are yet apparently
in a seryiceable condition. Experienced ordnance
officers say gun which will bear firing even 100
times without injury may be considered success
single ROdman hfteen-inch gun udS poo"
treated in the same way and is now undergoing the
firing test 1t promises to be quite as much Oh
success as the smaller guns. 1t has already STOOD
the test of more than 100 rounds. 1t viii be hreo
at least 400 times before the test is considered sat
isfactory. Each round costs about 800. In iact'
tho total cost of fringa single charge Is nearly
twice that amount but as the projectie is the most
costly portion of the charge, and can he recovered
and used agaln, economy IS secured III TINS way.
This expense explains the necessity for action Oy
Congress TO enable the work of experiment TO 90 on
hundred details in the construction OF carIlaees
and the machinery for stopping the gun IN sts le-
coil etc, are at the same time the SUBJECTS Oh eA-
pertinent and necessarily OF expense
| IL is estimated that pr0icctile from converter
Rodmau of eight-inch calibrc will penetrate an un-
backed iron plate 77lO inches IN thickness al uis-
tance of 900 yards. The proectlle from sno1th-
bore eght-inch gun would accomplish only nan as
much The penetrating power OF the eIe!eh-ihch
! converted ROdman will be equal to something more
than eleven inches of solid unbacked iron armor-a
force deemed sufic ent TO destroy any vessel Whch
| could enter the harbOrs of America.
The Chief of Ordnance submitted estimates ioI
the next fiscal year tor the purposes or experiment
| and the conversion OF smooth-bores into rnes
amounting to 1886, 600. The bill, n 1t has passed
| the House appropriates 1928 OOO-a sum winch
will 90 a very snort way in the direction or equip
ping the forts with artillery, when the necessary ex
| nense of testing shall have been met