The Charleston daily news. [volume] (Charleston, S.C.) 1865-1873, 1871-07-29

was assigned to this duty. and careful search
through the late reports of the Smithsonian
Institution fails to disclose the name of Pro-
lessor Aolus.) Nc longer.
"-celSd Sedet EolnS arce
Soeptra tenues,''
though ne still .,,,,,o >, ,.,,,.,.n, ,r, q,
of the ...,.... :,
~Having received my impressions concerning
the Office and the manner of conducting busl-
ness there from the report of Mrs. Jupter's
famous visit, from which these extracts are
made, was not at all prepared for the cordial
reception received, nor to find that so great
revolutions had taken place and 80 many in
provemeuts had been made since that report
was first printed. Instead OF "Vast cave,
within which the winds and storms are comm
ed, bound down with chains, and held In sub
lection by the 'sweight OF lofty mountains piled
Upon them,"I found an ordinary three.story
J brick dwelling, on the fiat roof OF which bad
been built sort of summer-house, supporting
on lis top certain black, odd-lookiug machines
immense weather-cocks. curious Wtnd-nllls,
with little cups on the ends of their long, slen-
der arms, and faring tunnels, such as may be
seen around still house or corner grocery,
except that these were larger. From an upper
corner window issued dozen telegraph wires,
which, having crossed the street, separated
and took diverse directions. No loud COM
plants nor deatening roar OF imprisoned winds
issued from bolted and barred iron doors, but
the entrance stood invitlngly open.
THE INTERIOR.
Within everything was as mysteriously plain
and commonplace. A parlor has been con.
verted into an Office by the introduction Of
two or three desks, at which sat as many gen.
tlemen engaged in writing. Some curiously-
wrought Implements standing In one corner
alone suggested the character OF the place.
Nor was the presence of the clerk himself any
more imposing. A room which, with Its books
and tables, had nothing to distinguish it from
thousand other government offices in this
city, was occupied by quiet, gentlemanly
officer of the army, to whom was presented.
General Myer, the chief signal officer, sits on
IL ''hieh throne" and bears aloft no ''sceptre,"
and yet his command over the winds and
predecessor in Office, with all his clustering
fuss and show, as his manners are gentler
than those of Eolus were.
There Is nothing of mystery about the chief
signal Office when once you are IN. visitors
are cordially welcomed and, accompanied by
partmenL, where all the instruments are care
fully explained, and questions cheerfully an
sBered. The business Of every signal station
Ia the country, as well as OF the central sta
ton in Washington, is divided Into two
branches, the making of observations to send
of reports and the publication Of them tor the
public use. Besides this, in the Office here,
. the reports, as they are received, are arranged
y 80 that they may be scientifically examined
and deductions made.
THE IEsTRUMESTS1THE BAROMETER.
First Of all, the observations must be made.
The instruments used Sare q barometer, ther-
nnometer, vane, anemometer, ian Instrument
for measuring the velocity and force Of the
wind rair-gange, and hygrometer, an In
strument for measuring the humidity Of the
atmosphere. The barometers issued to the OBJ
servers are superior instruments OF the ordl-
nary form; they are carefully compared with
the standard in the Washington ofdGe, and the
instrumental error ascertained. All readings
of the barometer taken for telegraphic trans
mission are corrected by the observer for tenn
peratuIe, elevation, and Instrumental error.
Careful instructions ere also given as to the
location OF the instrument and the method Of
rometer, and also Of the wet and dry bulb ther.
mometers, is registered by means of photo
graphy. so.
-Jehe thermometers used are ordinary stand
ard instruments, carefully corrected by COM
parsons with that from which the record is
made here. Observer sergeants are also sup
plleu Will IueTluoWetolS, WuCu ioSiSIeI uio
highest and lowest readings of the day.. They
are of the ordinary kind, one filled with mer-
curry, on the surface of which Is placed bit of
metal; as the mercury rises, 1t pushes this in
dex before 1t, but on falling, leaves 1t at the
highest point; the other. is filled with alcohol,
and .he index In this Is made Of porcelain. AS
the liquid recedes, the index is drawn along
by means Of the attraction between them, but
when it rises, 1t passes the index, leaving 1t at
the lowest point. Each day the index is placed
on the surface of the mercury or alcohol, the
one by means of magnet, and the other by
raising one end of the instrument
HYGRoNETERs.
The hygrometer consists of two thermome.
ters placed opposite each other on the same
LIN, and Is connected with little cistern of
water beloT by means Of some bits of cotton
yarn. TIE water Is thus raised by means of
capillary attraction so that the bulb is always
wet. The rapdity with which evaporation
takes place from the muslin on the bulb is in
dicated by the different readings Of the two
thermometers, and the amount OF moisture In
the air Is computed from this by the aid of
tables prepared by Guyot. The two thermome-
! ters are placed on the same frame, and be-
tween them is fixed an Index; small index.
connected with the large one in the centre,
also slides on the tube Of each thermometer.
When the srpall indices are SO placed as to In.
dictate the ~ ,ect reading ofthe thermometers,
percentage of moisture which the atmosphere
contains.
.ASEaoNETERs.
The thermometer consists of four small iron
nbfnispheres attached to the ends of two iron
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