The New York herald. [volume] (New York [N.Y.]) 1840-1920, 1878-06-06

count OF the disposition OF the bottom andtnat Il
cannot lead safely 10 Sandy Hook lghtship.
the lines OF equal depth, by sanay Hook latitude
running almost ~ parallel manner with The oast Of
Long Is and Nv. 3 VII Il is very obvious that west
ing error united TO southing cannot ,e dis
covered by s0undDgs and that Is easy 10 irae sew
erai parallel tracks toward the west ono thesouh
exactly, with the same distances between then, but
with differences toward west that Is TO say, tward
danger New jerseys bcachl; differences Increasing
more and moro IN proportion as the tracks aremofe
and more south.
that ships run their course. Five or miHs OF
southing difference give 10 or IL westward fr the
81 depth OF water.
Besides 10, IA ana even 10 and IL fataoms
found this course at 20 and 80 miles IRON sandy
HOOK but they are also loud At Tor 3 miles from
the shore How shall we distinguish clearly the
former from the lattcrY
BY the quality OF the bottomS
In IN my Cases 1t ls very poor means oil dirocion
have often heard seamea aud pilots praise the io
lowing custom:--
When OF Fire Island steer N. w. til Is iat hens
ard then steer w. 5. W. for stopping IN IL OF IL
iathoms. when you think you are At a good distance
IRON sandy Hook. This custom, quite Of roullne,
is AS uncertain as the direct course ana condemns
itself
10 navigating u snip one should dot believe think
when 1t is possible TO do otherwise ana TO know
exactly. -.
All The ships which grounded thought themselves
MAKING land UPox BROKEN TRACK
Having stated the danger. % a. least the uncer.
tainty, OF making land ~ soundings with direct
course, incertitude processing FROM The dsposion
OF the ground, us We cannot change THIS DIS oihon
"
with This disposition OF the grouud II We wish 10 and
In souudlngs The means oil settling exactly The posi-
tion u snip whatever may 20 me error o. NIP
brought from open sea and the direction oil tne cur
rent
Let US mark apparently the chart the limits Of
Is. 20 and 30 fathoms curve line
Let Us suppose a ship 10y dead reekoning) at loo
miles from sandy Hook, npoD 40 min. 20 deg latitude
Let Us allow her an error IA latitude, 10 milo. n or
Is MN j., aud IN longitude such error, east or
as 10, 20 80 miles, or more. this ship steering
Her locus or ma.nemat,caI hxlty shall bsiimiled
n. ana s. by 40 deg. 40 min and 40 deg 10 NM Let
steer $. 65 deg W. TIL sue strikes 10 TO 20 IN hons
The first locus Of the ship shall DC y, A. b,
The second locus (wben she strikes 10 20 iathoms
snail be a mere line; this limo c. q. Az moment
he latitude shall DO included between AZ deg ana "
deg o. mn. and the longitude n BET, - aes ~
have been original errors upon tnoss two elements
BY The single alteration Of tho course at the hrst
sounding 10 10 20 fathoms the WIDE and indclnite
surface A b, A b. shall become n short line O. U,
ana the in longitude shall not BIO greater than
THE SAFE COURSE
When having discovered tne line CO, steer n.
uruc) Upon This track tho depths will increase I'LL
the snip strikes again 20 faihoms, when she VIII meet
the olncr limit oil % fathoms While steering n.
the fourth locus OF the ship VII DC ID, " d. and
III king 20 athons again the Nth locus VIII be d. d.
But the distance run N. between the two sound.
ings OF 20 ialhoms, Inscribed INTO Inc locus d.
g d, WIN give he exact position OF these TWO
oundngs The latitude OF the last shall be inevitably
40 deg II 10 40 des IL min., ami The longitude
Will be liked al anu 3 mnutes.
IL 10 then possible to proceed with safety Tor the
sandy Hook Ligh ,ship
Lei Us remark nrst, That in the vicinity Of d. tho
limit oil 10 iatnoms very close 10 the unit OF the %
iathoms anu forms bank included within range OF
the Navcsink Light
or yailey which cxtcnds Ill co.e 10 sandy HOOK
Ligh,snip, IN which hoes may be iouna among
tho soundngs deeper than 10 fathoms.
Let US proceed now rom ID, I'VE or six miIos n.
NV. urue) will give IA fashoms Or iess upon the bank
WITHIN rcacn OF Navcsinx Lishl There the ship
should DO stopped wnen casierIs WINDS prevai--good
position Tor waiting Tor Gear weather
weatncr Ia spite Of ios, mp may go on for
From souad,ngs OF less than Is iahoms stecr W.
Vrucl sounding very frequently ~ aud the valley,
out 60 not cross II without sounding. When the
lead gives more imam 10 iaihoms from 10 TO ~
! p,rnaps) steer n. prue) xeepnr more than ID
| ,anons: a. soon az Inc water Is less than al
athoms anchor the ship and she will not DO far from
SANDY Hook Liahtshp, ready TO cross the bar when
| the weather clears up
| Firsf-l did MOI =. cas- oi mui holes which may be
ouud N u soundiogs; they are certainly very good
uaication when, by chance the lcal tails in the
snip must take advantage vi OUT 70 seek tuese no "a
wonld DC long ana ickiish work, while one may be
course directed That requires but some attention
| Sccond-rhc nrst sounding OF 20 tatnoms searched
for, bevrr the uCe position OF the ship Is known, II
least 20 mules from ine shore Tue snip may there
| lore seek u wllnout fear
Third-rnc track which 10 nearest TO land-tho ont
nortn 10 the Valleys rec from danger, since u u
4 parallel 10 The coast.
Foarh--ii, when dead reckoning places the ship 70
lees Eau IS 10 80 ntuoms the iod continues 10 gave
| more tnAh 30 lai hons IL may b. inferred that ~,
ship very sou,h tmorc south, perhaps, man 40 deg
10 mi, J, aud tue course must be w. N W. ttrucl III
- TO 10 ahOms, re-enterng so into the second loo al
4 b q, 81 C'--iound by experience.
| tUth.-Durins the way NJ IN u ID, O. d., the leat
| may by chance STRIKE upoh lamp ~ to 20 athoms
| wing close to the mud hole oil 81 iatboms out INT
sounding cannot cause mistake, since the aeptns vii
increase afer passing IL Il should be rather a goos
| Indication.
/ PERSONAL ExPkRIEscE
Sixth - tried lnis method the Sth oil May, 1877
Tho result was as iolowss-Sctting out Mt Sh. y. N
| IRON position wrong by IL miles, arrived Mt III y
position differing two miles from the one gwen bl
| pood bearings, the chip being at that moment y
| miles IRON sandy Hook Iiahthousc. Had not tim
| enough that day 10 do more.
| Scren1.-l tired again the 4th oil March, 1875 tw
days no observations nothing but soundngs; brougn
the ship three quarters OF mule N.N.E. of Sand
Hook hghtship, 10 ialhoms
| SPECIAL CASES.
We have supposed IN all former accounts that To-
took the ship about 100 miles from Sandy Hook, IN
| n frequently happens that tho ships meet fog o
two hours, Tor even afow moments before reach ri
FIRE Ireland light or coast ana that 10 the worst cas-
because they have taken no precautions and are no,
| IN less than thirty Iathoms OF water.
In this circumstance, like in others the only moan
| OF having "a irue guarantee will BIO to discover
| fathoms upon c., no matter how annoying u ma
DO not TO continue the direct course when close
| the end
we will consider two cascs:-
| FtrsL--Fog arrives; soundlngs are moro than
| fat hons (between 20 anu 2jl Continue W. Till
fuhoms, tncn steer B. (true) 10 miles, and then ses
| s. 65 w. flruc) tor reaching q O.
| Sec0nd Fog arrives. soundings are less tnan
fstnoms. stesr ). ttrueh. aud when the lead ind
Gates 20 iathoms continue 10 miles more, then stes
" VS. L. TRUDELLE,
| french Transatlantic Steamer france.
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