MONTHLY WEATHER REVIEW CHALBLES F. BROOKS, Edltor.
-- -~ ~. ..- . .. - -~ .. . . _--_ . ._
VOL. 4s No. 13.
W. B. io. 728. DECEMBER, 1820. CLOSED FEB. 3,1921 ISSUED Ma~.10.1921
ATMOSPHERIC ENVIRONMENT AND HEALTH.’
By Dr. LEONARD HILL.
[Osborne Hoiise, Loughton, Essex, England, Dcc lS, 193.1
The wild animal which survives in the struggle for existence enjoys perfect fitness and health. On the other hand civilized man requires a volume to contain the list of diseases from which he suffers. Not, only wild but domestic animals-horses, cattle, sheep, swine- do well on an open-air esist.ence; they are ftw more sub-
ject to disease when closely confined in stalls. Stock breedeis have not succeeded in using successfully arti- ficial heat for the raising of stock, escepting the case of young chickens 1ia.tched in incubators. The esperience of keepers of zoologicid garclens has led them to estend the opportunities of open-nir life, in the case of animnls brought from tropical countries. Man, evolved some million years ago, has immense in- born power of resisting cold. The espericnce of ship- wrecked people, and of citizen-soldiers esposecl to the utmost ri-ois of weat-her in the trenches. shows this power. f i l e soldiers in the great war, well-fed, clothed and esercisecl but at tiines wet, chilled and eshaustecl by mar, were, coniparecl to the civilian populat.ion at a t home, escept.ionally free from respirst.org catarrh. Wild men, such a.s the Fuegians, stand esposure to most inclement weather with scanty or no clot.hing and no houses or artificnl heat. They pmctice infnnticidc to keep t,he population down to the food supply. T h y , like the wild nnininl, shelter in thickets, or caves, where. owing to wind and temperature difference betwcrn their bodies and the atmosphere, there is free exchangc. of
air. The esperience of open-air schools 2nd sanat,oria show
. that life spent largely in the open benefits the health of
those subject to catarrhs, those wit.11 overncroous teni- perament. those with heart weakness, etc. London has two and New York not less than 120 such schools. The Japanese have carried out their wonclei-ful devclopment of artistic escellence in craftsnianship in slightly built dwellin s with the aid, in cold weather, of nothing but
clothes and esercise to keep their bodies warm. On the other hand, the endcavor in the last century or so of Europeans and Amerieiuns dwelling in the colder climntes, has been toward building. draughtless houses itnd secur- ing inside these by artificial heating a climate simiitxr to that on a still, oppressive warm summer dag. The low cooling power of st,a.gnant a.ir of roonis nrt.ificiallg heated by radiators de resses bhe metabolism to a low level. In place of the gody being kept wmn naturally by tho stimulation of cool air esciting muscular esercise and mular activity and so enhancing t.he combustion of
f ood, it is kept warm by the blanketing effect of warm
charcon 7 braziers to warm their hmds at, dcpending on
stagnant air, so that sedentary occupations, amusements and rest can be cmied out in warm comfort and a mini- mum of open-air muscular exercise be taken. The body is fashioned by nature for the getting of food by ac.tive esercise, and upon the taking of such esercise dcpends the proper vigorous function of the digestive, respiratory nnd vascular organs. Conse- qucnt on this, too, is tlie vigor of the nervous system and keen enjoyment of life. So, too, the healthy state of joints, muscles and ligaments, and freedom from rheumatic pains depend upon proper exercise of the body, neither over use nor under use, either of which may be rissociated with mal-nutrition and lowered resistance to infection. The hothouse conditions of life suitable for the failing powers of the aged, the injured in a state of shock and those in the last stages of wasting disease are mistakenly supposed to be suitable for the young and healthy. The traditional fear of cold is handed down from mother to chiltlren a t her knee. For fear of their
“ cstching cold,” they are confined indoors and over- clothed. They are clebilitated and esposed at the same time to niassive infection in crowded laces: They re-
principles of growth which are founcl in milk, the youn green shootg of plants, grain foods with the germ an outer layers not removed by the miller. At the same time they require the stimulation of abundant open-air esercise to make t,liem eat and metabolize their food. Housshold espenses will go up as more food is eatcn by
children escit ed by open-air exercise to keep appetite, but an immense national ec.onomy will result from a healthy, vigorous, efficient people.
Mm, with his erect posture, has to withstand the iiiIluonce of grax*it;i, which weiwhs down his viscera and t,aids to m:Ae his blood md bo&- fluids sink to the lower parts. This influence is naturall;; resisted bg the tone of bha muscles, skin, and o t.lier membranes which by con- fining the body prevent overdistension of dependent l>art.s, and muscular oserciae, such as walking, and the cmscqueub deep biwat.hing. which together pump the bloocl back from tho c.apillaries and peripherial veins to tho heart, ctnil a t the same tinio most effectually massage t,ha ahdomiuul viscera. Such ninssage kceps tlie circula-
t,iou active through the bowels, liver, etc., and helps those movements of the bowels which further the proper digest,iori and absorp tion of food and prevent constipa- tion. I’ii!in turd bac t,erial fermentations, with come- quent poisoning, arise in the bowcl! fram lack of esercise, particularly in thosc who indulge in tho pleasures of the tablo. Food is taken b;;. these which is not absorbed and
quire well-chosen food containing all t K ose vitamines or
f
-
1 Snbmitte~l lor presentation belore .fmerican hIeie?rolngiA Sociely. Chhcn. 111.. Ilec. 39. 1~20. To be Iiubliahed also in the Intrrnational R d Cross Junrmf. See also “The
science r d veiitila!im and open-air trratnicnt.” Medical Hcz. Counc., Special Report SeTics, No. 52, 3 5 pi^., London, 1920; noted in Mv. WmTHsn REV., Sept., 1920, 48: 4984%;
arid reviewed at lcrigfh in &zturc (Loridoll), Jan. ti, 1~20, pp. (iol-(i03.
3169;-21-1 68 7
688 MONTHLY WEATI4ER IiEVIETV. DECEMBER, 1920
utilized. In others appetite is reduced by the sedentar? indoor life and consti ation aiid d ~s p e sia result w-it,li a
starved. The deep breathing cscitnd by escrcisc not only furthers t.he circulnt.ion and t,hc act,ivity of t,he bowels, livcr, et.c., but! seciires t.he proper func t.ioning of an adequate blood stream throuali all mrt.s of the lungs. Out of doors the skin is coolecrand hriecl by the wiid and water is evaporated from it-the wind freely venti- lating the c.lothes. The air on tho most calm alii1 oppres- sive day out of doors is iicver as still as it is in a shutrup room. The skin is also warnioel b,- the ratlitint. encrgv of
the sun, and this, too, ac,tivc!\; causes ovapurnt,ion. Tho
wind and the sun affect t.he flow of water from lymph and blood through tlie skin, t,lie wind cools the blood in one‘part, t.he sun warms it. in another, t,he sliortor sun ri:\.s
act c,honiic,allF on thc. white skin ns evidewed b;v. sunburn and pigmentation. There is rmson to t.liink t,liat thc skin is a great scat of procluction of iiiiniune substaiicos which protect us against iiifect,ion. Esposure of t,hs skin
to sun and wind has a profound effect upon it, niid tlirougli it on the health of the bod;;. C’ool winds insure tlie re-
moval of tho bodj- heat 1~1,- convcct.ion, and koo ) t.he
in greater volumc through the viscera; t.he sun and
warmt,h dilabe t,he cu taiicous vcsscls aiicl onhance tlie flow through the skin, and escitc! ,crsyirnt,ion. Tlinse bo-autl-
monotonous life spent in an cnviroiiincnt, of owrn-arin,
stagnant, aiid moist! air entmglcd in their clot.lios whcn peo le are confined in rooms, oft.en crowclncl, is contritri to t g ose natur+lly changing concli tions which pwt,ain 011 t of doors. The air which is hrenthccl int.o tlie lungs, whnL ever be its contont of nic:)ist.urc or its tonipcr:iturc, is breathed out approsirnntc.1; - at, bod;,- tcwipcmt.iiro nncl saturat.cd with moist;ure at, t.his t.omporat,um. Whnt mat.-
ters to the skin and respirat.or\- menibrsno is lint the
relative humidit)-, hub tlic nc t u d v a p r pressure of t.lin air which comes in contact, with it,. C’olcl sat,umt.ctl air is
escessively drf when wa.nnc?d up t.o boc1;- teinpar:iturc, and takes up much moisturo from t,lio hot\. ; \mnn saturated air (or cveii hnlf-sat,iimt.ccl), far loss.
The vapor presmre of s:iturtited air at. 30” C‘. is 0.96
nini. Hg.; n t -loo C., 2.16; nt 0” C‘., 4.55; nt, 10” C!., 9.21; at 20°C., 17.54: nt 30” C., 31.S3; nt 35” C ., 43.3;
at 40” C., 55.3. A cubic mi!t,cr of air o m hold npproxi- niatel-F as many granis of water wlicii snturatml as shown
kc thc vapor prcssure figures just! given. The I~rcatliiiig of cool air entds, then, much grcntcr evapomt~ioii froni respiratov membrane and ooiiscquent greentcr flov- of lymph through and secrctioii of fluid from it. The
membrane is bettcr washstl and kept clnan from infect- ing microbes b;\- such outflow. Tho Ircnt.liiiig of c.old nir entails, too, the arent.er flow of nrt,eriinl blood through thc membrane in or&r to key;. it w-nriii, niid at the snnie t h e warm the inhaled air. ignrc~us open-air csercise may increase t,hc volume bmathccl fire times, and thiv on a
cold da:; means far more blood, 1;;mpli aiicl snrrt?t.ion fluid washing the respirator;,- mcmlmnc. The open-air workor
is thus better protected, wliilc lie escapc?~ t,he ninssivc infection from “carriers” which occurs in shut-up rooms.
It is the bronchitic with clironic infla.mmstion and t,liose with acutc catarrh who should not expose t,liemselves to the change of B t.nios@ero botween room a.nd win t r,- out of doors. What suits tlic bronchit.ic inrid those in the state of i‘cliill” from infectious catarrh must not be tiikon
as suitable for the healthy.
condition of deficient P eecling and the de P .)ility of tlii. scmi-
cutaneous vessels const.ric cl so t.hiit. the blood is c I riven
fro changes of t,he skin’s colic { it.ion nialio for 1ie:dt.h. The
For them dryness of cold air is not trying, for thc Alpine resorts are most bracing and hea1t.h-giving. In the sirocco in Palest.ine t.he relative humidity sank to 2 per cent, the t.emperaturc being 43’ C. In t.he Alpine winter midday blie physiolo&xl snt.uration deficit may be even lower, that, is, the clihx-ence het.ween the vapor pressure of the air and the vapor pressure of t.lie sir saturated at body temperature, t.hat- is owing to t,he stnall amount of vapor held in the air at the low t-eniperature there per-
taining (Dorno). One grain of water evaporated t.akes
awtty 600 calores of heat,, so the sweating mechanism is wry effect.ua1. but it must. fail in sattrmted atmospheres at tcmperaturcs tit. or near to body t.emperature. In hot, dry
atmospheres it, may become exhausted, especially in the sick, e. g., t.liose suffering from constipation, malaria, et.c.
d wet shtwt put on t.he bodv, and a fan set t,o blow on this, prevents lieat. stroke. in n hot,: dry ut.mosphcre by setting up an artificial evaporation. A hot., dry wind ma heat the body hy convection more than it can 1)s cooled g y. the evn.pornt,ion of sweat; t,o prevent! t.liis effect’ Arabs, in a smtlst.orm, croudi on t,he desert ancl cover theniselves wi t.h their robes. Moist., wurin atmospheres are trying
nncl recluce t.hc t+ficiency of workers, because of the diffi- cultv of get.t,ing riel of body heat. If the air is st,agnant, thc hycr ent.aiigIed in the chJthPs beconies saturated and raised t.0 skin tw-qm-at.ure. We t-bulb t emperat urcs in fnc t orics and mines are physiologically much more iniport.ant t.han dry-bulb t~cmp~rxturcs; so too the vapor-pressure rracling is much
more import.ant> than t.he relative humiility, ancl the vclocity of movement. of tho nir is most iinport,ant of all, for on this chicfly clepciicls cooling by convect.ion and evaporat,ion. The dry-hlh t.licrniomet.er indicates the
average effect of the teniperature of t,he tiir and walls of t,he inclosure on itself; it does not show t.he cooling and evnporat.ivc power of the environment on tho skin and respiratory menibrane. It, is ti stittic instrument while tlie body is dynimiio, producing licat wliich must be lost at. an e(. unl rate. To niensurc cooling aiicl evaporat,ive uwers, i have iiit,rotlriced t,~ie 1i:tt.ti t,licrniomet.er, a large- R d ~:)r r ~ spirit t1ierinoiiieter of stiinc1ml size and slinpe, gracluated between 100” and 95” F. The bulb is heat.ec1 in hot water in a Thcrmos flask until the menisc.us rises into the small top of t,he bulb. It. is then dried, suspended, nnd the time of cooling from 100” to 95” F. taken with 4
stop watch in seconds. The number of seconds divided into a factor number (approsimately 500, nnd.cleterminod for ench instrument) aives the coolinm owor by convec- tion ancl radiut.ion on h e surface of the ?P- hat.a” at appros-
iniately skin teni erature in millicalories per square cent,i- nieter per sec.onB The operahn is repeated wit.li a cot- ton niuslin finger stall on the bulb aiid the wet “katn’: cooling omer obtained, a cooling power clue to evapora- tion, rai‘iation, and convect,ion.
Thc difference bebween the two gives the evspor a t’ ive cooling power. power 011 t.lie top of observat.ories is from 30’ to 55” (Ff iii July and August, and about 40” (F.) in Deccnibrr ancl January. Est,ensive observnt,ion shows that the dry lint,ti” cooling powor is about 6 in ordinary rooms occii- iecl by sedent,ary workers. It. certainly should not be Ess t.lian exce ting uncler conc1it.ions of outside tempera-
%
ture which mn l! -e it impossible to secure such a coolin power by nieans of fan vent,ilation. t.o he as low as -1 and even 3 in fttct,orics anc 1 officcs when proper attention to ventilation would easily secure readings of 6.
In Britain t,he mean dry “ktt.a” coolin
L L
I t is fre uently foun
DECEMBER, 1920. MONTI-IT,T WEATHER REVIEW. 689
- -- .
Man.
When physical work is being done the reading should be higher, say 7 or 8 and even more when labor is being performed. By keeping t,he cooling power in proper rela- tion to the work done and heat out.put of the worker- four times as much energy is spent by the body in heat M
in doin external work-the latter can be kept from sweat-
ally stimulated to ive greater output.
drawing factorv, clusters of large air ducts have been installed over the heads and to the side of the workeis in front of the furnaces. The air current from these is so
great that when the furnace doors are shut one feels too cold and moves away. The men are warmed by radiant
energy and cooled by wind alternately as they draw the tubes from the furnaces or pause. The effect is as con- genial as the sun on a breez day corning in and out from
other factory of like lcinx, and t.liere is no industrial unrest.. An enormous improvement in health and efficiency will follow the general ap lication of a proper cooling power to the work in hand. &e heat output of different classes of
workers is eseniplified by the following estimates :
ing, an 5 working with conlfort and ease lie will be natur-
At Stewart & L 7 ogds, Halesowen, a large steel t,ube
white clouds. The out ut i ere is greater than from any
Additimnl k. cal. per hour r e qiiired for work.
~-
Typist.. .....................
Bookbinder .................. Howemaid .................. Washerwoman.. .............
Sewing mwhinist ............
~. ...... ..
Tailor.. ....................... Bookbinder. .................. ?I
24- 5;
35- ti3
S M 5 i
13l-214
......
~~~~
Yhoema kcr... ................. 90 Carpenter ..................... 116-164 Metal worker.. ...............
I 9 meters 4 rnrtprs I 1 meter
oiid 20 oiid S.8 ood. 2.2 per s e e per sec- per see-
miles’gcr milei per. milw per hour. how. j hour.
Temperature, O C .
Painter ....................... 145
................. Stonemason.. Man sawing w d .. ........... I E
0.5 Uictcr I
onrl, 1.1 Plil1:iir. milrs per ”craro i hnur. i
Woman.
n ..................................
j .................................. 10 ................................. 15 ................................. 20 ................................. 25..... ............................ 30 ................................. 35. ...............................
- . ..... -
.\ddition:r. k. c31. pcr
hnur re- quired lor work.
62.0
53.5
45.0
36.5
m.1
19.5
11.2
2.3
How much groater is the cooling power of lvind tliaii of change of temperature in stagnant air is shown 1). the following:
TABLE sIs.-coo2indJ polrrr b?y radiation and co)1t3frlio~l it& wti/l;fdorics
per square wntimctcr p r scrontl f.rcrtcd on. dry ‘.kutu” sicijatc nt .X .P C.
[The loss by radiation is assumed to bf the same as in a rhamber, the walls of which arc at the given temprratiire.l
45.6 I 27.7
39.1 ! 3.9
14.3 n.7 Y .l I
2 .0 I 9.Y
19.3 s . L
16.4 i .1
6.t
1 .I 3.1
4.0 ! 1.7 0.9 I 0.4
1;::
I
I have calculated that bhe tailor would require a dry kata cooling power of 6, thc. carpaliter 8-10, the &one- mason 15, and the man sawing wood 18 to kocp liim from sweatinw. The ‘%atit” can be used as an anenioniet,er, tdie formula connecting temperature and wind with the cooling of the dry “ kata” having been. marked out in wind tunncls. The formula, as stated 111 my Rerort to the Mcdical Research Council on t,he Science of \ entilation and Clpen- air Treatment (Spec. Rep. Series 33 and 53 H. M. Stn- tionery Office, London) , was
Hie = 0.39 + 0.49 Jii
The above figures are calculated on this forniultt.
Renewed investigation a t a low range of velocities gave the following as nioru correct:
Hie = 0.1 a + 0.54
and for velocities below 0.4 meters per second
Hie = 0.165 + 0.42 ,h
The wet “katn” readin is found to be about 18 to 20
being done. In warm moist s inning sheds and mines it mny he as low as 10 to 12. T\e wet “kataJ’ reading is of great iniportance when t,he temperature approximates to l)ody temperatmure, and coolin by convection and radiation becomes greatly reducef. Evaporation from the wet “kata” depends on the vapor pressure and wind, and bhe lnttor has a very wat effect. A formula has
borne in mind that the “ kata” indicates cooling and evnporntive powers from its own surface, not from the huimn body. It,s bulk is compnralde to the body of a mouse, and is much smaller than t.he parts of a human
body. The ‘‘ kata” readiugs give valuable measures of cooling and eva orative powers, but not direckly mens-
The st.imulatin and suggestive linq of inquiry into tho
nicnt, opened u 11)- Prof. E. Hunt.ington, require to he
and evrtporative powers. An estensive series of observations on people sitting in ordinary c.lotlies indoois or outdoors es osed to tho
with tlie dry “kata” cooling power. The cheek tem- perature varies ureatly with es osure, e. g.; from say 35’
C!. in overffarin~act.ories, 33’ $in factories which do not feel c h e , to 20’ C!. or even lower out of doors exposed to cold winds. The clicek teniperature also has a close rclntion to the metabolism when people are exposed out of doors to cool conditions. Esposure to cold wind may double the metabolism of a man sitting at rest. His nntural inclination is not to sit still and feel chilled, but be active and keep himself warm. It is to this impulsion to act.ivit,y and raising of nietal~olism that open-air life lnr ely owes its beneficial effect.
E1 tlie wint,er c1iniat.c of North America the cold outside air when 1ientc.d up beconiea very dry and increased ernporstke power acting on t,lie skin indoors cools the body. T h e isJ too, no source of intense radiant heat (a fire) in the rooms, thus high temperatures of 70’ F. or more are habitual. If the air could be moistened, lower temperatures would be found adequate as in England where a tempera- ture of 6 3 O F. is considered sufficient in an office heated by hot-wat,er mdiat.oiu with natural ventilation and no sensible draft, or wit.11 a plenum system. l n the Tropics there is requircd the building of houses so that through draft is everywhere obtained, with wide verandas (ventilated), double roofs wit.h ventilated air space (tlie vents screened to keep out animals), whitened walls, fan ventilation. The clothes must be of the liuhtest testurc and worn widely open at neck, sleeve, and %nee to allow ventilation. The skin should be allowed to pigment so that a gauzy material can be worn without sunburn resulting. Sloep should he taken on roofs where convection and radiation heat losses are greatest; a mat should take the place of a mattress, a cradle over the body covered with a sheet kept wet by a
in rooms which do not P; eel close where sedentary work is
also bee11 worked out for t f le wet “kata.” It must be
iircs of tht? con P iug and ovnporntive loss of the body.
relat,ion of lien f tli to weat>her and atmospheric environ-
cnrriocl out fart, f ier 1vit.h att.ent.ion t.o readings of cooling
wind shows that the metabolism is correlate B very closely
690 1MONTHLY WEATHER REVIEW. DECEMBER, 19‘10
spray or drip, and a fan to cool by evaporation may be used in hot, dry weat,her. The diminution of protein food, which stimulates metnbolieni and heat prodiiction, is indicated. Monkeys fed on rice ancl ripe haiinnns stand exposure to tropical sun out of dooiu. The taking of vigorous outdoor esercise keeps men much fitter in the
Tropics than women shut up and cooking in houses. The
body weight can be diminished to sis-t,entlis of the pre- war figure safdy, according to German reports on the effect of the blockade on the civilinn population. A
diminution pclrticularly of heavy weights in t.he Tro ics
increased in pro o r t p to the mass of the body. In England beEef 111 the open or gas fire 39 a source of radiant warnitli is justifieil. The moist, nust\-, mild weather is thus counteracted. Gas fire must replace con1
firpa to secure ecoiioniy of cod enFrgy and remove the all of smoke, dirt, and destruction of vegetable life
rrom the t.owns and the great loss of health and wea.lth these entail. The theory that chemical purity of the air is the one important thing h n s erlnit,t.ed the estah-
office rooms lighted DV wells, etc.
is an obvious advantage, the surface exposure being t a us
lishment of slum cities, i.ndergrount Y plnres of hsiness,
It must be redizeh t.lint the c.nrlmnic acid is never
not forthcomin to be exhaled infection from physical state of the
these are the agents The garden citv proviilea ootdyor esercise to be tttkeu in games and gardening, and the int,erests nntural to most men of perfect.ing the homestad a i d raising st,ocl; and
plants. Rabbits and fowls yield piotehi food, goat,s yield milk, and this and the green foods secure ani \e
supplies of essential mino acids and vitriniines. &e
man with his eight-hour clay at t.he fact.ory has his leisure filled in by reductive work and he and his family are
kept well fei, esercised, interest,ed, heixltlly, and 1:appy. The arden city with its fnctories is t,lie niaiii solution of
he& % troubles of civilized people. With the g u r i h city must go discipline, t.lirou@i education oi’ tlie P O U I I ~, in t,he
simple ways of keeping fit ancl enjoying life.
NOTE IN REGARD TO INDOOR AND OUTDOOR HUMIDITY.
In the discussion of indoor and out.door humidity and temperature and its relation to disease and health, found on age 504 of the MowrHLr WEATHER REVIE\\: for Sep-
tem f er, 1920, the following point,s seem to hnre been overlooked :
(1) The kind of indoor heat is not stated, whether steam, direct-indirect, hot air, or st.ore. The “coninlon
home” is usually heated by st,ove or bg hot-air furnace. Country schools are heated by stmes. The fluc t.uat,ions
of temperature and humidity woulcl be greaber with such
heat and would more nearly correspond to those out- doors.
(2) Praeticallg all the indoor temperatures cited are
above what has been accepted as the optinium for hunian health and for mental activity, viz, 65 to GS”. New
York State inst,itutions are now required to keep the temperature at this figure. The cla.t,s cit,ed would seem to indicat,e that the heat was by steam nnct the tempera- ture intended to be kept at about 73’. It ran up as
high as 89O; the lowest was 64” F.
(3) The relative humidities are correspondingly below the optimum.
(4) If the indoor temperature is kept near the opti- mum of 65 to GS”, the indoor relative humidity will be higher; the body will not be constantly overheated; there will be less contrast between outdoor and indoor temperature. Sweat.ing of the room walls will be much less apt to occur when the indoor humidity is high. (5) Movement of the air in the room is a factor that is kportant to comfort and healtli.--John R. Weeke.
NOTE IN REGARD TO THE PRIMARY CAUSE OF COLDS.
I t would seem that the conclusions of Dr. C. M’ Richt,er, in 1913, uoted in the MONTHLY WEATHER
primary cause of a “common cold” are not in accord with the most recent medical thought. The espired air from the lungs is normally near the saturation oint when it asses over the mucous mem-
per se, can not cause a discharge from and congestion of the mucous membranes. The air commonly enters dry and passes out moist.: therefore it can not b e a change from di to moist air, per se, that would cause cor za.
these differences. In recent studies of ventilation the effects of breath- ing satmated and humic1 air for varying periods have been observed. Breathing warm, saturated air whibe the body .is immersed .in. i t raises t,he hodi temperature, causes disc.onifort, and is in urious if t ere is no air c.irculation, but has not, I beiieve, been shown to cause irrihtion uncl hypersecretion in the mucous membranes
of the nose and throat. Similarly, experiments have shown that chilling of the body surface cnuses an ischemia (nnzemia) of the mucous membranes of the nose and throat instead of n hyperemia as was formerly su posed.
greater prevalence of colds with cyclonic- weather tha.t weather has macle dust which the winds
causing niechnnical irritation and bacterial implants- t.ion and growth. An am lification of this phase of tlie subject is given by Dr. Oyiver T. Osborne, rofessor of
on the “common cold” that a pears in the Handbook
the American Medical Association. If we define a “common cold” (acute coryza) as an inflammation and congestion of the mucous membranes of the nose and throat, then the best medical evidence is that a “common cold” is in the great majority of cases caused by bacterial invasion. If we n.sk what causes or
allows bacterial invasion, the answer is too lon diversi-
~~E V I E W for Septem a er, 1920, page 507, in regard to the
hranes of b K e nose a.nd t! Rr oat, therefore saturated air,
Even t 1 e liyperesthetic membrane is nccustoniel to
It may be suggestec! in explanation of the o 1 served
Eave carrie B from the streets to our nostrils an+ throats,
therapeutics at Yale ITniversity, in an exce P lent articlc
of Therapy, third edition, pub P ished by the Journal of
revious dr
fied, and complicated for these pages.-John % . Weeks.
CLIMATE AND HEALTH, WITH SPECIAY REFERENCE TO THE UNITED STATES.
By ROBERT DE C. WARD.
[Presidentid address before the American Meteorological Society at Chltago, Eee. 3,
(Author’s Abstract.)
1920.1
In the statement of the objects of tho American Mete- orological Society, the relation of nieteorology to the _. ._
1 To be published partly in the Sciratifie Molonfhly and partly in the Bouton Mcdical rird Surgical Journal.