New-York tribune. [volume] (New York [N.Y.]) 1866-1924, 1881-04-26

The Navy Department L. not precisely thr quart r
to which tlr public would incline 90 loph for nr"
disro,,ri. 10. tprtatIon Is that oi - 'oWi"Ftabi'
ra.y-g.ius Institution. welded {" routine and irldi
tom and chiefly occupcd IN hc'pinga few old hunks
aln.t which hardly amount % thu phantom Of a RAJ
uaYnl armament. OF late. however. the Depart
rn,ui has shown tigns of fresh life It, Chlrl-En-
ginrcr Mr. sherwood has been investigating new
motor at the Washington Navy -lanl. aud las
printed an interesting report as preliminary re-
suit Of his labors It must have required consider
able courage 10 enable him to take hold Of m inven-
tan in this line after the exploits Of that mpudcnt
and = r>istcnt humbug kcrlry. with his tumbcr-
fnU of water. but he has done il, and In,
frport holds ont strong hopes of success
that will startle the world The substance with
,hicL he has been cxpcrimcnting Is ammonia. The
inventor Of . machine for using thi, liquid IN the
production " ice led by his experiments to he
love that the difficulties which have hitherto
pr, vented It's application To- tn production of mo-
tive force could be overcome 10y mechanical con
irivanccs. The Navy Department had ut first taken
an interest in the icc-machine with view to its
use in killing the germs OF yellow fever on ship
board by Refrigeration, aud the new possibilities
developed in the investigation led the naval officers
10 obtain the consent Of Secretary Hunt Tor further
experimcnts which are now IN progress
Ammonia Il converted into gas nnder high pres
surrs al ordinary atmospheric temperatures and has
about thrre times the expansive force OF steam.
While water requires tho consumption Of snie lent
incl t. bring 1t up to the boiling point before rs ca
uacity for work. developed. ammonia puts forth IT.
pnwcr at q temperature no greater than that Of sea-
wafer. Heretofore. the difficulties in all efforts to
u,c the expansive force OF this sbstaucc have been
10 dispose Of the gas after it has acted on one end OF
a piston. 70 rcconYert II into hqmd, ana 10
rrturn the liqud Ia the receptacle from which
il comes under pressure in the form of gas
Chief Engineer sherwood thinks these difficulties
hayo been overcome 10y the inventions OF Professor
John Gargrr. with which hs experiments are
being made. la his description of the ammonia en-
CINE hr SAYS there ~ high pressure boil rwhcrc the
liaud ammonia is converted into gas by the heat in
water If atmospheric temperature, and low-prcs
SURE boiler - herr ammonia is kept 1T "a considerably
less tension than in thr other With this lower pres
sur ea the engine l.. operated. the gas b,n; usrd IS
eXpansi,ry ~ possible and made to do the work Of
moving the piston during IT, expansion thereby be-
coming refrigerated greatly reduced in bulk and
pariiaIly liqncfcd The cooled and shrunkcn gas
and liquid are discharged into the low-prcNsure
boiler hy an oic,tor worked 10y the higher pressure
i'm the high- pressure boiler. A. a INSULT the low
measure boiler is continually receiving ammonia
and heat frum the Ligh-prr7.urc boiler This excess,
of ammonia IN the liquid form IA pumped from the
low pressure back to the high-prcssnrc boiler while
the excess Of heat II continually being converted
into the mechanical work done 10y the engine.
Tho plan. argues the Chief Engineer. is based on
well demonstrated thermo-dynamical principles lilo
goc. ON 10 say: THE whole is definite and precise,
both in theory and mechanical detail, nor can 1t be
shown pro that there not fair prospect for sue
cess There can bc no doubt that the product Of the
pressure and volume OF the contents of the CONDENSER
which are 10 DO forced into the lowpnssure boiler,
il less than the product of the pressure and volume
Of the ammonia gas which leaves that boiler to OPP
crate the engine, aud that this difference. which Las