Weekly national intelligencer. [volume] (Washington [D.C.]) 1841-1869, 1854-10-21

nary circumstances, but particularly was the wan
felt during Gains and hot weather, when scarcely
breath of pure air could be conveyed into the cabins and
holds and when the vessels were crowded with human
beings emgrant vessels usually are, in spaces pro
portonally less than the law allows for the
lodging houses In rough weather Also when the port
holes were closed and the matches batened down. the
condition of the emgrans became infinitely worse for
the feted atmosphere which they were compelled to
breathe superadded consequent sickness fevers
and other cognate evils.
These consequences frequently fatal arising to the
poor creatures from such state Of unfavorable cond
ons too well knsn to require particular illustra
ton. An example or two however, might be given oil
the fatal effects which if not directly produced
tlinly greatly aggravated by want Of the for
proper ventilation and for dsinfecng the vessels. He
referred to the ship Dirgo, which lately sailed from this
port for Australia with emrants and in which, two days
after she left the port cholera broke and carried of
fortytwo passengers. In letter published in the pa
per5 time since account given OF the hor
rble condition Of the in the Government ships
in the Black Sea- where the cholera broke out during
stormy weather when the matches were batened down
and the portfolios closed The f0tid state of the ato-
sphere in these ships from the want of ventilation and
the ghul mortality that ensued in consequence,
most graphically described in that letter. These
were sufficient to illustrate the defective ventilang
employed board not only of merchant vessels
but the best appointed men-ofwar or Government
ships 1t might be safely asserted that no efficient ys
tenn of ventilation could be carried out in ships by any
other than motive power proportional to the require
ments of the number Of people board. All other
means such wind, Sails and open ports at present
employed could only be but partially effective and could
either all times be made available The scheme
which he mr. Cunningham suggested for eectng those
vital objects board vessel was illustrated by draw
ngs and had been made the subject of patent By the
application Of this power constant and most effective
method Of ventilation could ct all times be carried on
In combination with it, ALSO simple process Of dis
injecting ship (should Infectious distemper break
out) in most effective and rapid manner and had the
ALa Gave oI .~4 IL
been provided with the for yentlatng or dsin-
ecng them which his scheme embraced the probability
was that the cholera would not in either have made
Its appearance at oil events its vruent character
would have been greatly mtgated and the mortality
considerably lessened.
A statement appeared in late number Of the Med-
cal Journal Of the salutary effects produced by the
of chloride Of zinc dsnfecng agent among patients
laboring under yellow fever, showing that where the
chloride used five per cent. only Of the patients died.
whereas where it not used thirty per cent. died.
The recovery Of the patients also greatly promoted
by the Of the dsinfectng fluid The plan Of the
CINE shown by Mr.. Cunningham to the section calcu
lated at threehorse power, and sufficient to thor
oughly venate ship of 1900 tons burden, containing
six hundred persons and to afford to each person three
cubic feet of air every minute This supply is eff
fected by two fans performing four hundred and fifty
revolutions in minute thereby forcing the air down the
main ar-shaft to the side trunk fues, which extend
along each side of the vessel Small branch ues to the
cabins and other parts Of the ship requiring ventilation
are Joined the main trunk fues each being provided
with sliding revolving ventilators to regulate the
quisite amount Of supply By placing few bucketulls
of ice per diem in the tank the water may be cooled to
low degree and consequently the air must be reduced
in temperature in like This may be applied in
the tropics, when required The cost of providing
seana-engine boiler and apparatus complete including
ues &c. for ship Of 800 tons burden, similar to the
plans exhibited estimated by the lecturer at between
ESQ and G300 The quantity Of fuel required to keep
the engine work night and day for hundred days
would be about twenty TONS In addition to the process
of ventilation it proposed also to adapt the engine
several other purposes such the loading and dis
charging of the vessel lifting the anchors pumping the
ship supplying water to the watercosets and for clean
ing the decks and besides this it proposed to apply
the waste steam to the purposes OF cooking.
VARIATION OF THE MAGNET.--In the Geographical Sec
ton Sir j. Ross noticed, with less reluctance than
concern that the very elaborate article in the Admiralty
Manual the subject Of the variation of the magnet was
completely variance with that the interesting
topic by the Swedish Baron Wrede. This, he said might
be satisfactorily accounted for by the total disregard Of
solar and artificial light in the various observations
which had been made and published in the Admiralty
Manual Consequent on information no had given to
Baron Wrede of the discovery he had made OF arth-
cal light having the power Of amalgamation with mag
netsm, the baron totally excluded light from his mag
nete observatory, with the exception of subdued light
at considerable elevation vertical to the horizontal
needle while the arc read off by telescope, at
distance of several yards from the instrument 1t
evident that the deliberately the magnetic needle
was suspended Gas described in the Admiralty Manual
the more obnoxious it would be to the effect Of artificial
light in the operation of reading off the instrument This
would fully account for the many discrepancies therein
mentioned and it was to be hoped that in future due at
tenton would be paid to the fact discovered by Sir John
Ross and fully corroborated by Professor Tweede
Of which discovery the author Of the article in question
appeared to have been totally ignorant. Baron Wrede
would it stated in due time publish his observations
which would no doubt be transmitted to the Astronomical
Society In proof Of the effect of every description of
light the magnet Sir John mentioned that during his
last voyage in the Felix when frozen in about 100 miles
north Of the magnetic poe the rays Of the
full moon the magnetic needle, when he found it was
Eve degrees attracted by it.