The Iola register. [volume] (Iola, Allen County, Kansas) 1875-1902, 1881-08-26

CcuG. Will du cucCG ny uO IucduS pleas
ant. 1t was sultry, s'muggy" day,
while on Thursday, the 18th, the Their
mometer rising to much higher point
(90.4 deg than on the 10Th, the hui
Nudity was much lower, ranging from
81 to GA per cent. only, leaving the heat
much more endurable. This latter day
was in fact a remarkably pleasant day,
though over ten deg. hotter than the
former, and this was not due to q
stronger breeze, as the Signal Service
thermometer (wind measurer) registered
the same velocity of the winds from
four to ten miles an hour on both days.
The sensible difference in the two days,
as respects the comfort of the body is,
therefore, traceable to the great humid
ity of the air on the 18th and the smaller
degree of moisture on the 14th.
The term "relative humidity or
humidity" it is true, does not refer to
the absolute quantity of moisture in the
air. In the language of meteorolOgists,
the term humidity" denotes the de-
gree of its approach to saturation in the
air (or containing as much as it can
hold). 1t expresses the proportion
which the amount of vapor actually
present in the air bears to that amount
which the air would hold if it was at the
point of saturation-when dew, mist or
rain is about to fall from it. When the
humidity is recorded as 100, the air is
completely saturated with moisture and
rain is imminent, but if reported at 70
it contains only three-fourths of the
amount requisite for saturation. For
tunately for Philadelphians, the average
humidity of the air here year, in and year
out is under IS, and we are exempt from
the sultry climate of many places lying
even in higher ATTITUDES.
1t is of great Importance for those
who would profit by the daily Signal
service reports to bear in mind the sig
nificance of its humidity" column,
especially in the so-called "dog days. "
The warmer the air is the larger be-
comes the quantity of invisible vapor it
is capable of sustaining and storing
away in the interstices between its
atoms. At the freezing point it can only
hold one one-hundredth part of its own
weight of invisible vapor; at the tenn
perature of SO deg, one eightieth part of
its weight; at Sc deg, one-fortieth part,
and for every addition of % deg. of
temperature its capacity is doubled. If
fully saturated at 80 deg. of tempera-
ture it contains 2.37 grains of aqueous
vapor per cubic foot; at 60 deg, 5.87
grains in each cubic foot, and at 80 deg.
of the thermometer 1881 grains. A fall
of temperature from 80 deg. to 60 deg.
throws down therefore nearly grains
of water for every cubic foot of air thus
chilled. A cubic foot of saturated air
under average pressure and tempera-
ture of 80 deg. weighs 495 grains (Troy),
of which 14.8 grains are pure aqueous
vapor. With the temperature verging
on 100 deg, as it sometimes does in our
"water waves" the atmosphere, at
saturation, contains as much as 10 3-4
grains of water to the cubic foot, from
which some idea may be. gathered of
the enormous rain fall possibilities of
tropical clouds, which, heated up d.
rectly under the fierce sun, are replete
with evaporation from equatorial seas.
As these watery particles offer resist
ance to the heat of both the earth and
air beneath them, which is seeking to
escape by radiation into the upper at
mosphere, they thus effectually prevent
the cooling of the soil and of the lower
aerial strata. While the 'srelative hu-
midity'' data in the Weather Bureau
bulletins do not give the absolute
amount of vapor in the air, neverthe-
less, when the percentages given are
high, or near 100, they show that the
molecules of vapor are coalescing over
head, and are forming with the air
atoms canopy above US which inter-
cepts the heat of the earth in its attempt
to fly into the clouds. The vapor pres
ent also prevents the body from throw
ing off the high cumulative temperature
thus engendered in our midsummer
weather depends upon several circum-
stances. Evaporation from the skin
and lungs is perhaps the most impor-
tant means the body has of reducing its
surplus heat, as DR.. Max Won Petten-
koffer, the eminent Munich hygienist,
has shown by the use of an apparatus
for testing the quantity of water evap-
Grated by men and animals. His exper-
ments demonstrate that men at rest
evaporate about two pounds only during
twenty-four hours, but on a day of hard
work four and half pounds of water.
Gin the first instance" he says, ssabout
2,O16 caloric units; in the second, ALSO
had to leave the body in consequence of
evaporation" and he forcibly adds:
s'This explains how it can be that even
with the hardest work our blood will not
become warmer, but sometimes even
cooler, and what powerful means of
cooling our body we have in the in
crease of our peripheric circulation"
Prof. Lortet, of Lyons, while ascending
Mont Blanc, found the temperature in
his mouth and armpit was less than the
normal, and became normal only when
he was at rest. But the cooling effect
of evaporation is exhibited on a grander
scale in the meteorology of the tropics.
Last year, for instance, while in the high
ATTITUDES of London and Boston the Their
mometer reached or exceeded about 80
deg, at the Island of Mauritius, living in
the ''steaming bosom" of the Indian
Ocean, within 20 deg. of the equator,
the thermometer never once rose during
the year over $50, and the register for
1880 shows that at the Island of Barba-