Richmond dispatch. [volume] (Richmond, Va.) 1884-1903, 1892-07-31
Rationale Of suns;rokes.


The great yapor-laden wave OF heat
which is now eliminating on the easter
side of the United States has made re-
markable record.
Emanating from the tropics and enter
ing the country by the gateway OF the
Gulf, il has in the last six days overspread
all sections from the Atlantic coast to the
Rockies. The indraught Of every barome-
trio depression moving from Montana 10
Maine has caused fresh pulsatiOn OF tor
rid air to surge northward over the Mis-
slssippi and Ohio valleys. and the whole
interior of the continent has been aglow
with tho tervor of the "hot waye,n the
mercury registering q maximum some.
where from 80 to 100 degrees Fahrenheit at
all points not famed by sea or mountain
breezes.
This torrid spell throws valuable light
on the physiological cause of summer
maladies, sunstrokes, and prostratlOns
which have so fatally abounded. 1t is
generally, though groundlessly, supposed
that the great mortality IN " hot waves
Is due 10 the relative humidity COR damp
ness of the air. But observations taken
throughout the country during the pres
ent hot period completely upset this in
ference In places at which sunstrokeS
and prostrations were numerous the rela-
tive humidity was far from excessive. Thus
at louisville on Sunday it ranged from
81 to So per cent. On Monday and
Tuesday it ranged at Boston from IS TO 81
per cent. at Philadelphia from "a 20 63 !;
at Providence, Il. J., 1t was reported on
Monday a. " not excessive" while III this
city on Tuesday from the morning till
r. NJ. it ranged from 10 to IS per cent, and
yesterday morning it was near 40. At
Chicago On Tuesday night It was down TO
80. At Charleston. 5. C., Sunday was re-
markedly hot, yet it is reported the
humidity was excessive, out there were no
prostratlons by heat"
Such facts show conclusivelY that sun
stroke epidemics are due not TO high
relative humidity but To an excess of IN
I visible yapor or O great absolute humidity
I combined with great heat. During mid
winter New York air ordinarily contains
about one and a half grains Of yapOr in
/ each cubic foot. while in midsummer
| 1t carries on the average seven grams in
/ each cubic foot. But during great warm
waves,n caused by the protracted
| flow Of tropical currents from the
| Gulf of Mexico and from the Gulf
| stream off the Atlantic coast, vast volumes
/ of aqueous yapor are piled up over the
! United States. At such periods the air on
! our seabOard Is loaded up with water in
the invisible form, the amounts varying
| from nine TO fifteen grains per cubic foot.
| The bodies Of man and beast are then en-
wrapped in the thick folds of this ali-per-
vading varor- blankets. as in the coils Of a
serpent, and. of course, circulation. resni-
ration, and other functions of the b. 6y in.
dispensable TO life are partially suspi nde /.
| Since excess of absolute humidity q. ~
| tense sultriness is the true rationale Of
| prostrations. sunstrokes, and the large
! troop of other fatal summer mala-
dies, physicians and health boards
should watch this meteorological fac
| tor with the utmost vigilance. Great at
| tentlon Is paid in hot periods TO publish
| ing the thermometers exact record and
the relatiyo humidity, which latter is
| strangely credited with playing an impor-
| tant role in the deadly oppresaveness Of
the weather. But il would be far botter if
all weather services would. IN summer, az
least. publish daily reports Of tine actual
amount Of vapor per cubic foot OF AIR al
all important stations than to publish the
relative humidities, almost totally value
less for hygienic purposes during the dog
/ days.