296 MONTHLY WEATHER REVIEW. AUGUST, 1896
was dissipated by several memoirs that established the fact
that the wind and weather were entirely subordinate factors
and that the spread of the disease followed the lines of travel,
especially tlie priiicipal steamboat and railroad routes, and
that, therefore, the germs were carried l y diseased illdividuals
or by articles that liad been used by or had come in contact
with them, and not by the winds. Of course the wind, in the
narrow sense, inay have carried tlie germs a few feet or rods
from one individual to another, but not for distances of niaiiy
miles. Several epidemics, such as the yellow fever, smallpox,
alld cholera, have been traced back to the direct inlportation
of their contagia (whether animate or inaiiinia.te) by hriniaii
agencies. Furthermore, it appears probable, from experi-
mental data, tha.t few disease gernis can maint.ain t.heir vital-
ity more than a few hours when freely exposed to t,he air and
sunshine, as would probably be the case if they were carried in
the atniosphere as minute particles of dust. Therefore we
think it probable that the winds and the rain must not lie
consiclered as the means by which diseases a.re spread between
places that are any coiisiderahle distance apart. The liniit to
which living gernis can be carried i n the free air is not yet accu-
rately known, but,is believed to be quite sma.11. Theupper cur-
rents of air carried the vapor dust from Krakatoa, in 1883-'84,
over the whole Northern Hemisphere, hut many nionths were
required to do this, and wh:tt little we know of the life history
of disease gernis teaches that they co'tild not survive the sun-
shine, the dryiie!ps, rind, perliap, the colt1 of the upper currents.
This is not t.0 deny that the winds and the ocean currents
can carry the coars(:r seeds of plants and fungi for ninny miles without injury; but the bacterial digease germe have a
far more delicate organisin than those seeds, and wha.t would
seem to be an allowable analogy between the transportation
of eeeds and gernis fails when applied on a large Rcale. The
wind niny carry the gernis to a great distance in the free air,
hut probably will kill them in so doing; local breezes may
carry living gernis a few hundred feet, but the diseased man
or the oonvalescent,or the clotliing and articles used by these,
or the water me drink, or the food we eat, may carry tlieiii
hundreds and thousands of miles. In the particular case of
.the spread of the epizootic and influenza epidemics of lS'iS-''i3
ainong horses and cattle it was shown that they spread against,
the wind, or when there was a calm, quite 11,s often as they
spread with the wind.]
The following estract shows the result of an extensive in-
vestigation by the medical departnient of the Prussian army
into the spread of the grip epidemic of 1559-90. It illustrates
what we have above said and shows that we must not exag-
gerate the influence of the lower winds or the upper currents :
If we now collect together the results of experience as to the spread of the grip in the German army, we find that the view still holds good which prevailed at the beginning of the epidemic to the effect that the influenza is a disease that. owes its origin to certain miasmatic external causes. On the other hand there does not appear to be any sure evi- dence of the influence of weather, climate, wind, or soil, or the season of the year. To the contrary the number of those cases in which the spread and the mode of s reading of the grip is to beattributed to hu- man intercourse, is consi&ral,ly increased by the experience of the last epidemic. It is not yet clear whether in this intercourse there is a
direct carriage of the infectious material from person to person, or whether the infect,ioii is carried by the intervention of inanimate ob- jects through the air. We are still ignorant ?f the real germ that causes the disease. A correspondent from Bavaria gives the following ex- ample which leads him to believe that inanimate substances may house the real germs of the disease and carry them far away: The medical officer of the'garrison at GermerRheim at& time when as et not a sin le case of grip had occurred at. t.hat place, received a paczage from
a $ace in Russia at which the disease prerailed sevcrel . A short time after opening this package he fell sick of the grip, angsoon after also his whole family. If it should be further demonstrated that dead sub- stances can thus contribute to tlie spread of the disease germs, then, perhaps in this way we shall explain the appearance of the disease upon ships on t.he high seas. The germs attached to the cargo carried b a shi can, b s reading among the seamen, give rise to a violent, suddren outlreak d tge grip.
Those interested in studying the distribution of disease and
in defending the general atmosphere from calumny will find
a mass of iuformation in the Handbook of Geographical aud
Historical Pathology by Dr. August Hirsch, translated and
published by the new Sydenham Society, London, 1883. The
data there given show that not only influenza but nearly every
other form of epidemic has a secondary dependence upon
favorable weat.her. Some diseases that are characteristic of
tropical climates have been known to break out in midwinter
when the ground is frozen a d covered with snow ; these oc-
currences depended upon t.he habits of the people, the teni-
perature and cleanliness of their houses, the food they ate,
and the water they drank, rather than on any special meteor-
ological conditions.
The "climate" of the sanitarian considers not merely the
mnligh t, temperature, moisture, and wind of the meteorolo-
gist, but many other factors that const.itute the environment
of man and have a bearing on health aid disease.
DO TEIUNDERSTORMS ADVANCE AGAINST THE WIND 3
The note from Mr. Hicks, published in the MONTHLY
WEATHER REVIEW for April, page 131, has called forth the
following letter from Mr. C. A. Perdue, voluntary observer, Be-
loit, Kans. (W. 9 8 O 05', N. 39O 30', 200 miles west of the Mis-
souri River), and tlie editor will be glad to obtain still other
notes on this point.
I n the report for April, which I have just received, I not.ice the state- ment of Mr. E. D. Hicks, observer at Marceline, Mo., of which I have heretofore seen no notice in print. This fact I have frequent1 observed since my residence here and can confirm his observation. 6 is proba- ble that the same phenomenon will be shown to occur over all those treeless plains so much above sea level when further observations are made.
THE CAUSE OF THE LOW TEMPERATTJRES FOR AUGUST.
Mr. George N. Salisbury, Director of the Washington State
Weather Service, writes in the August REVIEW, as follows :
This was an excessively dry month in all sections of the State. Practically no rain occurred until the rainy period, which began in the northwestern part of the State on the 19th, and ended in the east- ern part on the 21st. Prior to this the drought had been of six weeks' continuance. West of the mountains the average rainfall was a trifle more than last ear, but much less than that of any other August on rewrd. East ofthe mountains it was a trifle less than last year, and less than any August on record. It was the coolest August of which there was an record here, notwithstanding the fact that there was so
little rain an8cloudiness. This is probably accounted for by the fact that on many days that were otherwise clear the sun was almost en- tirely obscured by excessive smoke from forest fires, which extended over a great part of the eastern as well as the entire western section of the fitate.
[ NoTE.-The interesting suggestion here made has led the
editor to compare the mean maxima for August, 1895, with
those for August, 1894, and to do the same, also, for the
niorithly mean of the minima. The details, as given in the
followiiig tables for the eastern and western portions of the
State, show that, as compared with 1894, the average and
maximum temperatures of 1895 were, indeed, lower. The
lowering of the maxima might be attributed to the direct
etl'ect of .the absorption of solar rays by the smoke, but as
the miiiimiini temperatures were also lower, and that, too,
even niore so than the maxima, it becomes evident that the
obscuration of the sunlight by the smoke is not the only, nor
indeed the principal cause, of the average low temperature.
The data for s,urrounding States show that the temperature WB.E
below the normal throughout the Pacific Coast, the Platean
Region, Montana, and the Canadian Provinces of Alberta.,
Saekatchewan, and Manitoba. Over the northwest part of
this region the pressures were above the normal, and over all
of i t the rainfall was below normal. Everywhere, nioreoi-er,
the lowest minima on record were reported.