Wilmington journal. [volume] (Wilmington, N.C.) 1844-1895, 1874-04-03
Ch'I'n Com. Gil i,a,bor Imp 'mDAt.


JAI4.SON ) AUTOMATIC 5ELF-FEE!NG iA2!P
The following is 4 description of DIR.
S. X. jackson Automatic Self feed
ing Lamp, for producing u continuous
light for marking channels, ohstTHr-
tons TO navigation, &c:
The object OF the invention is 10
meet 4 great desideratum of the pres
ent day, viz: to produce q light winch
will bum FOR long period withour the
necessity Of trimming, and therefore
not needing an attendant. Fer Tie
buoys and spars, which are at pres 1T
employed to designate channels and
mark shoals and obstrTctiors to nHHi-
cation, It is proposed to substitute =
small structure similar to q pigeon
house, upon u single pile. iron uI
woOlcn, screwed or driven. Wh.:-H
shall contain on" Of these lamps, hold
ing OF! enough 10 last several weeks.
These structures are to h,' visited st
Intervals by the nearest Lighthouse"
keepers, or by an inspector appointed
10 sljpeciutend the several I:ght-iuuS5.
districts.
1t is supposed that these lights VIII
effect a complete r0voiution in our in
Land commerce, and will render tie
navigation OF our bays and rivers a
easy by night as by day, and II they
are made to exhibit different color&.
corresponding to the present colcrs OF
the buOTs, any one OF ordinary intel
Igence viii be able to understand
them, and to fad the channels without
the aid OF pilots. Che uniformity Of
light is effected by maintaining Il uni
form oil level, thereby securing r Uni
form pressure and an cGuable supply.
These objects are attained by having
body Of water, supported by pnou-
matte pressure, i'll ii tank placed above
the lamp; this tank Is connected with
the lamp itself by means OF Il tube
which terminates at the surface OF
bOly Of water in a lower vessel which
supports the OIL bylIy,lraulic pressure
The water IN the lower vessel is pre-
vented from rising too high hy an
overflow pipe, and Is prevented from
being too low by exposing the end OF
the tube from the superposcd tank,
which lets down Il supply OF water
upon the admission OF air !;y this
means a perfect water level IS main
tanned, and as tho specific gravity Of
the oil is little less than that Of the
water, the oil level is always Il little
above that OF the water, consequently
there IS always a supply of oil to the
burner.
This arrangement has been Tor some
time under the inspection Of the Light
house Board, and has been put III
practical use in Currituck Sound, North
Carolina. These lights have lasted
twenty-one days without attention, du-
ring the past Winter ; and although
they are III very eXpOsed situations
near the Atlantic coast, have not been
affected by storms.
The burner at present used affords
a light which can be plainly seen five
miles, (they have been seen twelve
miles,, and consumes onc-third Of n
gallon of oil, costing twelve cents per
gallon. Of course, the saving of that
portion consumed during the daylight
(say the one-half OF four cents, would
not justify the employment of a man
to extinguish and relight.
The annual report Of the Light
House Board shows that they have
throughout all our waters about 5000
unlighted beacCns and buoys actually
in position. If for each of these one
Of the structures above described were
substituted, the current expense Of
lighting them would be, at the calcllla-
lions given above, about $12O per day,
or less than So, 600 per annum. This
expense is insignificant compared with
the benefit of making them as service
able by night as by day, which is really
doubling the sailing time Of vessels.
An outlay of about one million of dol
lars for the construction of as many of
these lights as are needed for the
whole country, and an annual expen-
diture OF about One-third the amount
now expended in repairing and replac-
ing the buoys, is all that is required
to confer such benefits upon our COM
marce.
OFFICE OF THE ALEEEThRLE
& CHESAPEAKE CANAL. Co.,
NORFOLK, Va, Mar. q, 1874.
1Nessr8. 4. D. CGgue'r, Wilmington ::
Dear Sir:-I have yours of the 10th
inst. We have placed several of DR..
Jackson's lights on the line of our nav
igation through Currituck Sound and
have found them useful aids to navi-
CATION. Some of the lights have run
as long as nineteen days without being
visited by any one. In fact, the oil
was entirely consumed when it went
out. In consequence of not having
any one to care for them, they have