The daily union. [volume] (Washington [D.C.]) 1845-1857, 1849-05-05


sOn the 2sh March, the British sloop Of war Calypso,
anchored in this harbor take in water direct from Cali
forna She had board half million OF California
gold She reports that provisions were scarce IN the gold
regions that much confusion and robberes existed and
that there than one hundred Americans re,
naming at Mazaan, whose means had gwen out ana
were unable to pursue their journey further
[Corresp ondence Of the Philadelphia nquerl
WASHINGTON CITY, April 81, ls49.
SIR Having in your paper OF April 10. notice OF
Fresnes Dioptrics lights" which contains covert,
ha .1 bat little light Of the Whole
quantity produced, is made available" have thought
few truthful statements, in regard to the two systems,
might be useful
The catoptric or reflector lights, in general for
lighthouses, the coast of the United States For
several years past effort has been constantly exercised
change the personal administration OF our light house
service, using the doprc lenticular apparatus as
stepping and for this purpose the most erroneous
statements have been made both to persons and facts
which, though repeatedly exposed, have as often been
With regard the loss Of light the best lenses utilize
not quite four ffths of the light for in calculating at
nine enhs, omission is made of the quantity intercepted
by the framework holding the lenses In the reflector
light, about thirds of the light is utilized. The
amount of intense central light utilized is the in
both, being the whole mpingng those surfaces What
lost in both systems, is the feeble crcumferenn hgh
which, impngng at small angles OF incidence spread
over relatively larger surfaces, and gives but slight ef
fertso feeble in truth to be entirely lost at medium
distances The light from the crcumferentia parts is, in
TACT, worthless IN practice IN Doth systems
! The real merits of the two systems may be briefly
compared under the heads ofrst COST cost OF personal
attendance, cost Of oil, efficiency size of the light, and
distance at which it can be seen To make this COMPARE
son. will take lens light of the second order and one
OF corresponding reflector lights OF twelve lamps
that being the average number OF lamps in our light
houses ewing to the whole horizon not requiring llum
nation at their particular localities.
First cost for encuar apparatus, $4,000 90
lantern, Nager than for re-
! - $500 90
&c reflector light apparatus, 30, 80
complete, 300 90
s2aso 90
Difference of frs, cost. $3.50 90
Personal attendance for lens light, keepers at o %
@''.p'' "'."'''' reflector, 400 90
Difference of cost of personal attendance per - -
Cost OF oil for lenticular light, 600 gallons at 81 per
reflector d" 420 80
Difference in cost of oil per annum 1870 90
first cost Of light of the reflector light
by $3.50, the interest of which ar q per cent per an
Difference Of cost OF personal attendance per :.
Difference of cost Of oil per annum 100 90
Total difference expenditure for light 1880 90
Now there about 300 light in the United States
and were encuar apparatus introduced IN place OF inc
SYSTEM the increased expenditure would amount no.
The actual expenditure of the present system. in
Guiding administration service, repairs, floating
lights. (much more expensive than fixed onesD ~ o
From which it will be perceived that the introduction
of the lens light would nearly double the present annual
expenditure and would there be any more deficiency
From numerous evidence it har been established be-
You'd possibility Of doubt that the reflector light is seen
as far and shows greater mass or size OF light than the
lens light and this results from their mode OF consuc
ton In hred lens light of the second order, the mass
OF light emerging from the lens is zone about hve feet
broad and consequently meets the eye OF the observer as
only vertical line; while the reflector light presents
mass equal to the of two circles OF twenty one
inches diameter or 4sl square feet With the revor,ng
reascors Al New York Rarbor, there can be seen the
Highlands of Neversink Lights they are entcular appa
rans of the first and second order placed side by side
moment OF FASH volume of light sufficient to complete
overpower the light from the eebler fixed lens though
of greater size But revolving lights of great pract
darkness left between the flashes and if these be lessen
ed by increasing the speed of rotation. there results pro
portona dmnuion in the intensity of the light and the
revolver loses Its superiority
The reflector light Sandy Hook is adjacent to and
ible at the time the Nevefsnk lentcuar lights.
The Sandy Hook light gives intense and larger mass
flight than is given by either OF the Others for any dis
lance the three be viewed at together. The Never
sink lights having elevation OF 24S feet above the
while that at Sandy Hook is but 90 feet are Of course,
visible farther, owing to the of the earth.
Further the suboned extract from minutes OF evidence
taken before select committee of the British House of
Commons in ls45 having the celebrated Joseph Hume
for chairman, is conclusive the question of "eficen-
cy" The evidence given by committee of the
elder brethren of Trinity House, and is signed by their
secretary.
cat o'clock, p m, Monday, 10th October, left tho
habor accompanied by Mr. inspect the light
on the Isle OF May, which reached al hapast and
landed The temporary light the that had been
re from inchkei'h In the lantern two circles
o. rehectors, ii in each, and the lighthouse
French fixed lens light, with of looking
eeow and seven nbove, with twenty in each tier and
,.o eAacuy IN the same way at the start The
Is rather small being only III feet inches but the
is OF the first order. Arranged with Mr. Ste
venson TO have all the argnnd lamps lighted the direction
. and e. and at seven took leave of Mr.
stevenson went on board and steered 8. s. E. keepin
the new light which the highest open 10 the west
the iow and continued that until il could no longer
be seen from he deck, which IS minute. nine
During the whole time that the tights Wis BILE together
which was M minutes past 9, when the light was
put out 1--WE having not be kent
lighted more than an hour and half after we left the
sandD they were 80 exactly alike that IL was almost i'm.
possible discover any difference there were anv we
thought the light from the reflector rather the largest thai
,koxs hax y