Macon beacon. [volume] (Macon, Miss.) 1859-1995, 1873-10-11
Relation Of the Air to Clothing.

The following statements Of general
interest are specially reliable, beingcon-
in a lecture by Professor Petten.
boter, Of Munich, whs is known as high
authority on such subjects Although
the warmth of the body is the result Of
respiration, it is a singular fact that the
normal temperature Of the blood Of the
African is the same as that OF the Esaui-
max, or about 99l degrees, while the cir
surrounding them, and inhaledby them,
may differ as much as 1870 degrees in
temperature neither does this temper
aturc vary, in q state Of health, more
than two degrees, though the tempera-
ture Of the sirmay vary 72deg, TheLeat
generated by the body in twenty-four
hours is sufficient to raise thirty quarts
Of cold water to the boiling-point and
of this the regular processes of nutri-
ton require only a definite part, ana the
larger portion must be giveuof through
radiation, evaporation, or c~onductiou.
When heat is lost by radiation, as INST
ting near a cold window, or other cold
object, the impression Of draught may
be created, although the air beperiec'ly
calm, heat being simply given mp TO the
colder object. Thus, while the tenn
perHture of a room may remain cou-
slant, different sensations may be cype-
rieneed, dependent on the surrounding
objects. Amuch larger amount Of the
superduous heat is lost by evaporation;
and during severe exercise, when more
heat is developed, evaporation is also
more rapid, and the normal temperature
of the blood restored. A "cold' is
caught when theovaporation istoorapid.
But little heat is lost by CONJUNCTION,
The particles Of air in contact with the
body becomes warm, and are replacedhv
colder ones, creating a current, which is
iuseusible, because of less velocity than
three feet per second. III better con
ductors cooling takes place more rapidly,
water of 81 DIES. ees seeming much colder
than air of Ct degrees, These three
modes Of cooling, however, supplement
each other, and act together. Thus d
current of warm air cools more rapidly
than calm cooler air, not only by reason
of renewal of the air, but by favoring
evaporation.
The chief object OF clothing is to sur
round the body artiicially with a warn
climate, poor conductors being conse.
quentIy selected. The cooling process.
is, however, simply checked by the cloth
ing. Even the thinnest, faestfabric, as
q veil, diminishes loss by radiation. But
the iuclosure Of air is especially eIec-
tive, and consequently garments Of po-
rous heavy material are warmer than
those which are more compact. Felt
shoes, permeable to air, are warmert than
leather or india-rubber ones, while the
latter soon become uncomfortable because
Of checked ventilation. The more hv-
groscopic the material, the colder the
clothing, because il is a better conduc-
tor when moist. Linen and silk are for
this reason colder than wool, andalso be-
cause the latterretain It's elasticity when
moist, and keeps the air Within its pores.
And our bed, which is, in fact, our sleep
ing garment, is Of special interest. II
must be warmer than our waking cloth
ing, since less heat is developed during
sleep. Consequently loss Of sleep is
very e~Xhausting, The feath,r-bed pos
sessas in the highest degree feeble con.
Quoting power, elasticity, and permeo
bility to air; but, if too thick or soft
resembles more an air-tight garment
The house, too, may be regarded as az
extended piece Of clothing, 30 gradual i
tie transition from bodily garments tot
Cthe step from the vide garment Of thu
Arab TO his felt tent being a small one,
and, in hyRienic functions, they aHreD
precisely negotiating our relations with
the surroundingair. The ease with which
a current Of air may be blown through
q brick, pieces Of mortar, wood, etc, BY
glass tubes cemented to opposite sides
and the passage Of water 10 much den
SER through these substances. show hop
il perfectly Il walls, OF whatever ma
terial, and however thick, exclude tn,
air from u.s.. We do not perceive tn,
free passage Of air through them be.
cause the currents too slow, -Harper',
Mdqdziae.