The New York herald. [volume] (New York [N.Y.]) 1840-1920, 1857-04-09

ns re. h $500 pss,a vA,sA ~ ssvslss ssnus
PIE suu sCmTIFICAIAY HAHugm.
mo Ioalowns letter u nom Distinguished 0gine0
d ths ey, who has scisntiaeay sxanined Ne nedel
and t,swsS: = l s. .s' ,,. $1,000 NE,
pg and spsnng steamers FOR naSns service sVAoreuss
and sassiel asdy, sa = P.oIi.s1, I've 700 ss,say
pressed me- and which scarcely ial 70 ssswas saf
evident poiuen in any tudsnsu = ~ ntssd b si1dy
u" y whole, q ne system 20 s1vssals asd. NJ
hcpA are soon 70 dsmonstrate. II
:: q ysy %ss' ' 49,
ana are nss svidsnt . mere eE.haasS. Oonvsnisncs
perceived bat whAs d equally true Aos0h s apparent
Z that NE plan Of The two sspasats single ssguss working
II &c Sssn.i s.y you pssp:s ops 5:
door not only to large economy In Aru oosi for given
.svs po.s, e. the snp but stss' n s
thh port and certainty equalling IN Ah rpecs oar river
boats, TO which, In TACT your syie q hnll length Of
Yss Ce 70 he sdvsnsssss Of duposss nse enigma.
adepsed by you, The pc uliar framing end russng
ana s.Spa for .ss service en any .y
tenn now knswn to the pupic
In regard 70 your plan OF double wheeh 0ere u mag
ter invesved vastly more important and pomsng Of
moro impo tant yesultA ShAn any one would, oesve,
redit a. nrss glance.
ordinary duty, the ssmc may be said o. ice after
ones 10 far q the mere Of their concern
Important location mis- points to oOsssaueDoss scarcely
70 DO over estin aaed. viii endesvcs 10 de~orsrase
this.
Al vessel 10 driven forward, she PARIS or 1ypaces
the WAFER Ike wedge, and this may be resolved INTO
lifting hat weight Of ~ser from the dspih OF IL mean
centre Of gravity to her limo Of immersion IA time COR
responding that In which her widest Immersed cross
section VII travel . distance reaching 70 her bow here
prsssiou Of The .powor hsorssicsy szsrsed, VIZ Il.
given weight raiaed given distance N given time.
This power may be considered 70 be exered and supplied
shvor1w thA u0tuen r
The maxim has "aciiOn and 70 acsion are equal" 70
must close behind the shp, and sinoe even she
stationary, TIE pressure Of water asaines her stsrn
ss .vS :saos H.. S.. IN p pro- .. IL. n.
ac pressure and inertia Of the water o. her bow rssS
her moving forward, 40 mus: me wsssr :, ne. ssesn
without oonsideriug it, adhesion 70 her which
greatly exceeds in ~ power 70 reasd The frioon Of the
che tends TO leave . vacuum aitsr her, which only
prevented by gravity Of the water and tne pressure
Sss n: Sss Ss: ws:s s ss
xnd, furshsr viii DO sosn that whilst Me heroes shus
preventing the actual formation suoh vacuum remains
constant quantity, the tendency 70 form increases IN
an enormous ratio Win The speed, thus becoming
II this vacuum were supposed for osri 70 be really
equal 10 pressure Of fifteen pounds pss square sos On
the ars0 Of her mmtrsed GROSS section; but % the In
erua OF the water behind her stern W0ul0 De vastly ~
tbsn this also much less than her momentum,
70 pressed in toward her, - before sxplslned-Al d
which lvable into the Act Thai hc exists retArd
Ing power equal IN amount 70 power capable Of moving
spca quantity Of from atate Of Pert 70 speed
equal tbas Of the vessel in time equal 70 Va, which
she passes through distance oorrespocdne 70 tnas nom
her srsatest mmersod cross section 70 her stern
shos, however, vessel does MOI, m reality, produos
eve. partial vacuum IN ps.soe snrsssS We sss, s.s
far. fetched and insgninosnt, and % woud DO - IN m
significant speed OF the vessel bus - win 10 seen asr
noments reflection, Increases IN . tremon dou ratio
With the speed, - rn Dtoned before Practco proves ~
greet consequence, for ell know hat amount a
steam o. all can sve speed 70 cat wba sqnare sssra
md . short rum
Now here 10 whore your "ansT' paddles grssx
advantase They take the water just whore b coming
70 rest non The impulse hes received nom TIE torwaFd
whesh, and where ABOUT commencing 70 sdhere 70,
and IN sesse, "dras amer the sh,p-h c,osy words,
commsooes 70 DO "dsad vstor"
Thus these paddles the one hand pcs ouly hsve
nrn dip u comparatively smooth water, RUNNING
away from them but The osher hand they give This
waseR fresh impetus, carrying quickly rndey ana
beyond NE curve OF her run, closing her IN v,b Give
vassr," and greatly relieving her hon be sdboaon and
drag referedo