JANUARY, 1902. MONTHLY WEATHER REVlEW. 35
was no clisturbance as the meteorologikts developed t,heir view$
on the subject. Suschnig says: it was as though recognition
and thanks were due to science, and he adds, <It is to bc
hoped that the spirit which prevailed in this congress may alsc
inspire future congresses on this subject.
It is indeed true that ii recognition and thanks are due t o
science, for if it had not been for the strenuous cleiiiand on
the part of scientists in Europe and America that this hail
shooting delusion should lie examined into carefully niicl treateil
from R common sense point of view, we might have 1,)elielcl
the Congress at Lyons promulgating a series of illogical and
erroneous conclusions leading to a great waste of ~iic~iieg ant1
loss of life consequent upon the general acloption of the erro-
neous views that have spread so rapidly from Htyria ancl Italy
into southern France.
Science i n
only another word for truth and intelligent coiiiiuon sense.
On account of the clificulties of: scientific research it may cost
~100,000 to clemonstrate s ~i n e truth in nature. but! when QUC~J
attained miah truths liecoiue the basis for an iiiiiuenxe niuouiit
of saving in time, labor. ~iioney, and life. The sole object
of the scientific world is to get a t the laws o f nature in order
tn serve the best interests of mankind. Of course this often
niean iconoclasm as to old ideas and methods, lmt. we who
live on the earth, breathe its atnioqiliere and rejoice in its
sunshine and cloucl, can not afford to be ignorant o f the IRWH
of the material world nronncl up. It would lie a xnd corninen-
tary 011 the civilization of France if the nation tliat, has so
greatly profited by accepting the wonderful results of the re-
searches of Pasteur should make itself ridiculous by rejecting
c. A.
eENERAL REPORT ON HAIL SHOOTINa PRESENTED TO THEI UON(3RESS AT LYONS.
BY Prd. J. U. P I x N A x m ~s , Mct.runllal#ixt. of the i)jJSVIV:Ihwy a l f liiy-tl4~~11w.
[Tmualatd by Mrb. E. 8. IIirrm.]
Errors, like ignorance, are always espensive.
the equally important work of its famous nieteorolog wits.- 
Allow me, in the first place. to express iiiy regret, t.hrtt an
unfortunate illness has deprived our congress of the valuable
assistance of M. Ho~~ckille, whom I have not the presumption
to pretend to replace. In 1300 BI. Houclaille \van appointed
by the minister of agricultnuse to make a series of studies in
the wine regions of upper Italy, where the struggle against
hail had already attained extraordinary developent. 111 the
coiirse of his mission lie collected ~iiiineroiis and iiiiportaiit
documents on all the points relating to this question, and ptr-
titularly on the edcieiicy and tlie organization of tlie firiiig of
cannon against hail clouds : lie then sumiiiarized the publica-
tions on the subject which hac1 been coinmunicated to him, as
well as his own personal observations, and issued, through his
publisher, Alcan, t-i book filled with enlightened ideas aucl pro-
found and accurate observatiolis. Better than anyone else
was M. Houdaille fitted (and he proved i t in effect) to con-
tinue and bring to a happy conclusion the work that he liad
so .well begun.
It was therefore not without niuch hesitation that I coii-
sentetl to accept the perilous honor of attempting 60 fill his
place. I was induced to de HO, first, by the estreine kindiiess
of our president. 15. Burelle, niid of our general secretary.
M. Silvestre, and, finally, I relied upon yonr iiidn1geiic.e. liop-
ing that my twenty-five years of study of storms and l i d
woulcl escuse my temerity.
Moreover, in the accomplishment of my ta&, which lias
already been facilitated by the eminent reporters mho ]la\-e
preceded me, I shall littve in view only an impartial search for
truth, and I have already had the satisfaction of finding that
on all important points my opinions agree with those of M.
Roberto, the learned supervisor of education of the Province
of Aleasandria, who is charged with a report similar to my own.
I have followed the readiug of the reports with the greatest
attention and have also studied them at length. I have pur-
posely libstained from taking an active part in the discussion
of these reports in order that I may consider them as R whole
n-ithont an?; personal feeling and thus maintaiu the most
al.)eolute impartiality.
I f we wish to judge of the. results obtained against hail by
the discharge of cannon, fusees, petards, or any other method
which lias for its object the combatting against storms, it is,
of course, necessary to be acquainted with. the esperiments
that have already been made. But it is none theless necessary
to have in addition and aliove all, apart from all preconceived
t.lieorien, rational ideas of t.he atinosplieric conclitions which
produce hailstones. It is, nioreover, almost inclispensable, not
only to hare personally obser~ed a great number of storms,
but, it is also and perhaps still more necessary to have studied
them in their relations to t.he general conditions of the at-
mosphere. This implies the habitual use of the daily charts
which show both the absolute and the relative values of the
principal ineteorologicttl elenients in tlieir relation to thun-
derstoriii phenomena. But be not alarmed, I am not going to
theorize. I n the cluestion with which we are occupied you
very rightly place facts above all else. I will invoke only
these facts, and among them we shall find some that justify
the struggle that you have entered upon against hail.
In tlie remrtrknble reports that liave been communicated to
tis all tlie facts are interesting, but not all in the same degree,
especially wlien it is desired to invoke them as prosimate
proofs of the eiEcacy of tlie firing of cannon to prevent tlie fall
D f hail. Let 11s take, for esample. a case which lias been fre-
cpiitly observed: In a locality well organized for defense, a
3torm approaches unespectedly. By the blaokness of the cloud,
the darknexn produced by it, the intensity of the lightning, and
the continuous roll of t,liunder coming nearer nncl nearer it
wenis as though it mis t acquire es traordinary violence, and
iiienace t,he region with disaster. The artillerymen are a t
their posts, and fire the cannon methodically. Soon tlie
Jtrength of tlie storm diminishes ancl it passes away, discharg-
inp over the region only a raiu that is more beneficial than
harmful.
Is it the iiring of the cannon that has clissipated the storm?
rhix is not a1)solutely imposiible, but who can aflirm that it is
40, since dissipation occiirs very frequently without any cannon
I t all being fired? It woulcl be necessary to haw a very large
iuinher of favorable observations in order to place any confi-
Ience in such a bold assertion. It is about the same with those
tssertions that attribute to tlie influence of the cannon shots
rarions occurences that may really be quite indepenclent of it,
mcli as the diininntion of the violence or the frequency of the
wiucl, of lightning, thunder, or hail, the dispersion or defiec-
ion of storin clouds, etc.
AH proof positive of the influence of the firing on hailstorms
:he falls, of snow observed in a certain number of localities
luring storms combatted hy cannon have often beeu cited. It
s said that the repeated dischitrges of tlie cannon transfoimecl
;he hail into snow, or at least that they prevented the forma-
;ion of hail and allowed only tlie formation of snow. Here
igaiii tlie proof is not suficient, and these falls of snow are not
iecesaarily the result of the firing, as they are itlso observed dur-
iig stornix against which no cannon have been fired. More-
rver, $hey are of more frequent oociirrence than is generally
iupposed, particularly in mountainous regions where they ac-
!ompang a part of tlie storms of spring, autunin, and sometimes
hose of Sllmlller.
Snowstorms are of more frequent occurrence the higher we
mend in altitude, or the farther north we go in latitude, or

36 MONTHLY WEATHER REVIEW. JANUARY, 1902
again, the farther the season under consideration is from mid-
summer. This is very reasonable. But in our temperate
climates they also occur a t all seasons and a t orchary alti-
tudes. In France, a t the level of the slopes where the vine is
cultivated, they are not of yearly OccuiTence, although accord-
ing to observations of the Central Meteorological Bureau that
I have consulted, they are very nearly so, since from 1891 to
1898, it was only in the year 1893, which was estremely warm,
that they did not occur. Duiing this period of seven years,
snowstorms were experienced on 33 different clays, and itr was
precisely in the wine regions of the Rhone, Beaujolais, and
Micon that they were most frequent. It is in these regions
also that they occunecl at the seasons nearest midsunimer.
Moreover, the above figures give only the minimum values,
since all the localities do not cooperate with the Ineteorological
service, and many snowstorms have certainly occurred that
have not been reported. For example, I have discorered the
following dates in some Rcientific p&licdions: Tlie storiii of
August 27, 1896, at Albertville (422 met,ers) and a t FertP Mach
(206 meters) in the department of the Orne; one on Septem-
ber 19, 1897, a t Havre, and on J d y 31, 1893, a t Ohent, where
the snowflakes m-ere as large as a franc 1)iec.e. By innking
more careful investigations w e slio~zld discover inany other
cases, and if we do not meet with thein inore frequently it is
because in summer the flakes generally melt in the lower dratn
of the air.
On the yihole. one is obliged to adniit that according to all
observed facts, when snow occurs in summer i t is always clur-
ing thnnclerstoimis, so that these latter, notn4thstanding the
heat which precedes them, seem to favor the fall of snow. This
is certainly ti-ue, and moreover it is easily esplainecl. The warm
ascending currents that give rise to thunderstorms a t first
produce rain or hail, but in proportion as these currents be-
come weaker and exhaust themselves, the cold of the upper
strata finally overcomes them and congeals the aqueous vapor
into snow, and this the more easily the higher t,liey have risen.
On the other hand, the storms themselves, by inteimiising the
strata of air piled one above the other from the surface of the
earth up to a very great altitude. procl~ice, as i n well known, a
general cooling; if this cooling is suiliciently great! the snow
will descend to the surface of the earth without melting. thus
causing a very natural surprise, such as was lwoclucecl a t the
time of the firing of cannon in the vine countries of France
and of northern Italy.
I n conclusion, we see that even admittring that the cannon
produce a certain effect upon thunclerstorins, we coulcl not
attribute to theni the procluction of snow absolutely, and still
less, of course, the change into snow of a hailstone already
formed. The hailstone once formed of ice more or less hard,
can only be destroyed or rendered softer by the action of heat;
if the melting is complete, it then turns into rain. but some-
times into a soft hailstone if the ice composing i t is not suffi-
ciently homogeneous and is only partially melted.
It is moreover probable that the greater nunil>er of soft
hailstones are formed directly. For this purpose it suffices
that small masses of water in an unstable stnte of surfusion
be found in the inidst of the storm vortices, and that then con-
gelation should take place as the effect of a shock against an-
other mass of water, or an ice crystal, or a snowflake. or even
simply under the influence of a too abrupt movement,. I f the
general temperature of the inass of water in surfusion is not
sufiiciently low to solidify the whole, there remains some water
imprisoned hetween the crystals that are forniecl and the re-
sult is soft ice that inay be crushed under the least pressure.
The surfusion of water and the formation of soft hailstones
may be produced without much c1ificnlt;F by taking a few pre-
cautions, but I have often ol>servecl their spontaneous foi-ma-
tion while making use of the psxchrometer to determine in
winter the hygrometric condition of the esterior air a t the ob-
servatory of Puy-de-DGme. The water which serves to moisten
the muslin of the wet thermometer is contained in a small
cylindrical porcelain vase of a capacity of about 30 cubic centi-
meters. This vase rests habitually upon a small iron shelf
fisecl alongside of the thermometer shelter, in order that the
water may be about the temperature of the circumambient air,
and it is esposecl to the natural cooling that may be produced
l ~y convection or by radiation. As the cooling takes place espe-
cially a t the bottom, which is in contact with a metallic mass
that is a good conductor of heat, the water is not agitated by
eilclies and may remain liquicl even when its temperature i!
lowerecl to a litble below zero; it is precisely this phenomenon
which produces the surfusion of water. But when the bulb
of the tliermometer, which must be wet in order to make the
psychrometric observation, is clipped into this surfused water,
the 30 cubic centimeters of water is suddenly transformed into
ice that resemhles half-melted snow, because it imprisons an
escess of water that is not soliclified. This slushy ice is never-
theless suaciently solid to remain attached to the thermometer.
Thus, one obtains almost instantaneously a sort of soft hail-
stone, similar to those that fall cluring certain storms.
Here then we have a series of facts upon which, it seems to
me, too mnch reliance has erroneously been placed as proving
beyond all doubt the eficiency of cannon against hail. For-
tunat,ely, there are other facts which, although they still leave
much to be desired, yet, nevertheless, have more weight than
the preceding.
Among these is the general and persistent diminution of the
damage caused by hail, and which is considered as a conse-
quence of the firing.
diminution might still be only a coincidence. I n effect, even
for very estensive regions, and long before the filing of can-
non had developed, long series of observations had shorn-n
that the number of falls of hail, as well as the estent of the
daniitge indicted by them, are subject to considerable varia-
tions, sometimes in one direction sometimes in the other, not
only from year to year but cluiing several consecutive years
Here is an esample: The num11er.of meteorological stations in
the department of Puy-de-Dhe which suffered damage from
hail each year, from 1886 to 1893, was 72,32,4,18,8, ancl37, re-
spectively. If the protection of crops by cannon had been or-
ganized there in 1887, it would certainly have had attributed to
it this enormous diminution of damage which lasted five years.
I f we consider only a restricted region, and particularly a
single locality, we get still more fantastic or perplesing +e-
snlts. Thus a small conimune may not experience any notable
losses from hail for eight or ten years, and then again it may
be ravaged by it for three or foul. consecutive years.
What now is to be said of the strokes of lightning that have
occurred cluring the firing within the protected zones ? What
conclusion is to be clramn from the more or less complete dis-
asters that have occurred notwithstanding five or six thousand
clischarges of cannon, if not that they weaken the argument
for the usefulness of cannon as much as the favorable cases
strengthen it ?
Of course this does not indicate positively that the firing of
cannon fails to produce any effect :on hailstorms, but simply
that the preceding facts clo not suiXce to prove such action.
It is much more encouraging to cite the following among
the statements which justify attiibuting some influence upon
thunderstornis to the firing of cannon:
1. The sudden suppression of hail over the immediate bor-
ders of a region protected by cannon.
2. The immunity enjoyed by a protected region while all
the surrounding territory, or a t least a part of the region im-'
lnecliately adjoining it, is ravaged by hail.
3. The destruction wrought in a small noiiprotected zone
inclosed within a vast extent of country where the cannon
have worked well and which has not suffered any damage.
Nevertheless, while it is very real, thi
JMUABY, 1902. MONTHLY WEATHER REVIEW. '37
These facts have been attested by different reporters ancl
they have been brought to my attention more particularly by
Mr. Roberto who guarantees their authenticity.
But even for these three cases which seem to testify so
eloquently in favor of the useful results of the firing, it is still
necessary to make some reservations. In effect, when one has
at his disposal a large network of meteorological stations rery
near to each other, very instructive facts relative to the 15s-
tribution of hailstorms can be established.
When a storm is of great estent, or rather, as happens most
frequently in viticultural regions, which are ah-ags rather
hilly, when a certain number of storms (which seem indeed to
make only one) burst nearly simultaneously. we recoguize by
stud,fing the observations macle (1) that one, two, or seT-eral re-
gions get the hail either over the whole of t,heir territory or. at.
least, over greater or less portions of i t ; (3) that aaalogous
groups do not get any hail, either on the whole or on larger
or smaller portions of their territory; (3) that the two classes
of groups are in some way or other confused one with the
other. In such a case, it is very cliPuxlt to judge as to the efi-
cacy of the cannon discharges by the limits of the hail falls.
Indeed. if it is the communes that have organized the shoot-
ing that have escaped, they will be apt to sag that they have
been protected by the cannon; if, on the other hand, it! is these
communes that have been hailed on, then to be logical it must
be said that it is the filing of the cannon that lins caused the
hail to fall. I n the case of a coinmune that is only partially
affected by the hail, one is free to think as lie pleases.
Nevertheless in all of these three cases the cannon may haw
had nothing whatever to do with the effects noted. I n every
case, the utility of cannonading is, of course, much more prob-
able if the immune surfaces coincide esactlg with trhe protected
regions and if the ravaged districts also coincide with the non-
protected regions, always, however, on condition t,hat these
facts be proven a great number of times without serious or
frequent exceptions.
Certain less cominon types of stoiws have, however. fur-
nished a surer means of control, viz, those which being coin-
pletely isolated and possesfiing, so to speak, an individuality,
deposit hail along a narrow ancl rather long st,rip of country.
A complete immunity from chaster in a portion of the strip
protected by cannon, or a t least a complete cessation of its
ravages a t the boundaries of the protected zone, would justify
the hypothesis of a protecting influence. But here again, this
justification woulcl have to be verified a great number of times.
On the whole, among the facts invoked in favor of the effi-
cacy of the camon shooting, there are some that prove abso-
lutely nothing, others that are unfavorable, and only a few
can be made to serve as a foundation for the hypothesis of
the protecting influence. This is really good progress in
such efforts. The too enthusiastic persons who have be-
lieved in the prompt and radical suppression of hail will cer-
tainly be disappointed, RS is always the case when one cliscounts
too highly the success of an enterprise. But the more mocler-
ate ones will be satisfied with the single idea that the struggle
against hail is not absolutely impossible.
Moreover a great impulse has been given. The enthusiasm
which began in Italy has spread into France. It remains to
find out how to direct it, to regulate without lessening it, in
order to render it useful and profitable. For this piirpose, i t
is first necessary to be well convinced that in all experiments
whose purpose is to act upon nature, time is a factor of the
greatest importance. To wish to proceed too rapidly, impru-
dently, and without method, is to invite defeat. A great deal
of money, an immense aiiiouat of good will and work would
belost if people allowed themselves to be carried away by the
very natural, but too human and often illusory, desire of gain-
ing the victory with the least delay.
When we have seriously studied thunderstorms in their
causes and effects, with the aid of all the necessary documenta;
when we are able to account for the grandeur and extent of
the forces that produce them and regulate their course; when
we know the immense energy developed by them, it seems dif-
ficult, almost impossible-especially after the experiments made
by MM. Pernter and Trabert, Castine and Vermorel-to admit
that the souorous vibrations produced by cannon, bombs, fusees,
petards, eta., any more than those made by the annular vortices
thrown out by the cannon, can hape a nw~haiaicd. torce suEcient
to destroy such formidable phenomena or to restrict their
powers of destruction. NeverthelesA, Mr. Roberto, whose great
scientific attainments are well known, believes that he can prove
the possibility of accomplishing it.
But the esplanation of the efficacy is not the principal point
in this question. Whether this eficacy be the result of a still
niysterious influence, perhaps electric, unless it be some other;
whether science a t present can or c q not explain this iuflu-
eiice, we will not nt present discuss. From a practical point of
view what is above all most important to establish clearly, and
as proniptly as possible, is that the firing of cannon does really
protect the crops from damage by hail. Once this is proved,
people may esplain it if tsheg can, but they will first projit by
it, ancl it is the practical advantages that one should look to
at, present. On account of the paucity of convincing scientific
facts, or perhaps better-in order not to wound just suscepti-
bilities-on account of the strill insufficient number of con-
rincing facts, it will be necessary to make new experiments,
~n d I alii happy to be able to state that on this point I find
myself in agreeiiient with all or nearly all of the reporters
who have preceded me. These esperiments may be made de-
cisive within a very biief period; but in any case they will
become so sooner or later if we follow as closely as possible
the principles of scientific methods and refuse to accept any
fact, nnd above all aiiy conclusion, without having first sub-
niitkecl i t to a rigorous criticism.
I will take good care iiot to give any advice as to anything
relating to the tealiiiical part of the filing. In this branch I
should have everything to learii from those who have organ-
ized and directed it with so mucli ability; but I will take the
libert,y of calling your attention to some ideas which have
been suggested by m y long study of storms.
One of the first conclitions to be complied with will be to
establish in the regions chosen for the definitive esperiments,
a perfect serTrice of meteorological observations, . with the
active cooperation of the Cea t.ml Bnreau nncl the nieteorologi-
cal committees. Learing the exactitude of these observations
out of the clue'stsion, they will be of more value in proportion
as the stations are more numerous. It will be necessary to
have one station in each commune over a total area equal a t least
to that of a department, in order to be able to follow.up some of
the storms from their first beginning to their clissipation.' A0
a private indiviclual can scarcely know accurately anything
more than what takes place in the small region around him, it
would be well if these stations were placed under the direction
and management of the communal officers. They would
thus succeed without tronble in furnishing accurate, complete,
and well authenticated inforination in regard to all the phe-
iioinena relating to storms throughout the whole commune.
The great practical interest that attaches to this question of
hail would certainly ensure the active cooperation of each
municipality.
Again, t,he disposit,ion of the cannon over the region to be
protected woulcl have to be regulated Eviclently, if the cannon
had a s u e ancl indisputable protecting influence, there would
he nothing to do but to distribute the greatest possible num-
her over the region, being guicled. of course, by the pecuniary
results. But i t is necessary not to lose sight of the fact that
French cnmniunes and dspiti-tiiirnts compare to American townships ~i i d counties.
38 MONTHLY WEATHER REVIEW. .JANUARY, 1902
.the eficiency of the shooting is 'far from having been clemon-
strated to the satisfaction of every one and our object is pre-
cisely to prove it to a1L
During the past year, two particularly interesting communnl
organizations have been formed in France: (1) A t DenicEt
(by Messrs. Guimand and B h c j where 53 cannon have heen
placed about 500 meters apart, in such manner as to form n
regular defense over the whole surface of the commune, tlie
geometrical outline of which is almost that of a rectaiigle
twice aa long as broad; (2) n t Saintm-C+engous-le-Nntional and
Burnand, where the attempt has been made to plnre the can-
non along the ordinary trajectory of the thunclerstoriiis. I n
the north of Italy, a certain nuinher of escellent iiistnllnt,ione
have been made accorcling to the same principals.
The Denicee type, for esainple. wonlcl haw to be developed.
aucl it would be aclvantrtgeons to organize n regiilnr c.ontinu-
OUR defense over a territory suficiently vatit in propnrtiun to
the area covered by bhe storms, ~i i d coiiiprisiiig :J group of as
many contiguous coniniunes ns possible. This has nlread~
been clone by Mr. C!liatsillon, in the region of Beaujolais; he
has established 18 shooting stations with a total of 340 c:mion
and covering an area of 10,000 hectares. There slionld in nd-
ditioii be selected other commmial groups without caiiiltm, but
presenting about. the same ngricultursl and t,opogrnpliicnl coil-
clitions as the preceding. ani1 thus, by a siniple coiiiparism, it
would be seen whether the storiiis in geneml behave any differently in the two groups of coiniiiiines. This, of ctxirtie.
would not prevent the ordinary obs,ervntions froin being mnde.
The Saint-Ckngonx type leiids itself to e still more int,erest-
ing modification. Suppose that i t should he desired t.o innlie
an application of this type in the depnrt.nient. of t.he Rlioae.
which woizlcl be perfectly approprinte for the purpose. by
reason of its extent, its geographical positioii. its tqmgrqjhy~
the seiious damage that it sustniiin each year, .uld also on nc-
count of the cannon that nre nlreaclg est,nldislied there.
In this department, as also in many others, tlie storms i i i o ~e
in general from the west-southwest to the east-northetlst. or
perhaps rather from t,he suutliwent to the iiortslieast. I f tlie
defense were organized by mnltiplyini,. the c?aiinoii in that direc-
tion, and consequently dii~inishing the number in tlie other
directions, the hal>itual limited breadth of the st.orms \vould
cause them to pass nearly always either to the right or the left,
of the line of defense; they woulcl tondi it lightly soiiietiiiies,
but would rarely reach it completely. The action of the can-
non would then, howeyer, be very ilifficult t o interpret,, and
one would often be exposed to unfortunate illiirrioiis, and
sources of e i ~o r that would seriously diiiiiiiisli the value of the
experiments.
On the other hand, these grave defects could be avoicled bg
extending the line of defense over a long strip of territory
which should be perpenclicular to the ordinary direcbion of
progression of the storms. This strip of country iiiight t>e of
any desired width, but should above all be quite long in order
that a large part of the storms should be obliged to cross it.
Thus good comparisons would be obtained between the effects
produced by t.he storms in this protected strip. and those that
they caused before they encountered the c.aumm, and after
they passed them.
Many improvements will still be in troilucecl into the iuethocls
of protection fiom hail, by experienced persons w110 ]lave
directed the former esperiments. But tliere is one fault that
they shoiild carefully nroicl falling into, namely. that which
would result from the dissipation of our energy. It wodcl be
puerile and injurious to iiiultiplg incwiiiplete orpniiizations
which would do no good and would conihce t,o discourage-
ment. At present, all efforts shoulcl be directed to n single
end-to proving in an irrefragable ninnner t,lie eflicncy of can-
non shooting against hail; and for this purpose it is necessary
to accuinulate well authenticated facts. The enthusiasm that
~~ ~ ~~ ~~ ~~~
you have manifested proves to me that it is not necessary for
me to bid you be of good conrage. To the work then, and let
us hope for victory.
WEATHER BUREAU MEN AS INSTRUUTORS AND LECTURERS.
We print herewith the outline of a course iu climatology
that is being giren by Mr. k E. Hackett, Section Director,
C'olmiibin, Mo., to students in the University of Missouri.
With regard to t,he method of instruction, Mr. Hackett
says :
In lldiillg the wwitiiis charts the data is rend by the instrur-tor and iqiivd upim lilitiik m i t p ~ liy tliv studrnts, the iwthlrrinh itnd o t h ~r lines
lwing tlmwu ~lnring the \verli.
A 15-iiiiiiutr qiiiz is given ~n r h week upon thr rhnits and lectnre of thr Iwrrrdiiig W P I ~
A FOURTEEN WEEKS' COTTRSE IN CLIMATOLOGY.
[C'i~nfi~ird to n. study l b f thr climate of the Unitrd Statra.]
FIRST WEEK.
Lwtrrrc..-Hoir tiw driinxI~1itv-a is litxfed: brief reference to the
lniiicildes of ci ~niluct~ioii. convection, radiation, aiicl reflection,
the amounta uf s( )law heat rec*eired by the Northern Hemisphere
at difierent senhons of the year, different effects upon land and
w&r surfaces. diurnal fluctuations of temperature, effects of
oc'eiui iwrrentx ani1 large bodies of water upon the tempera-
ture of adjacent laiiils. effects of altitude, prevailing winds,
etc.. roiiduction of lieat in soil; ?/o i /i tAr f P i n p w t i i r r i f t l i r nir is
mosirrcd; iroir tile rrorrirol farripmftrre fiJr m y plrcr is ohtrtitit~!.
XEC'ONI) WEEK.
('hnrf i(v~~-k.-Aiiniial mea11 temperature of the United States.
( 7iort /rorX:-Normal teiuperatures for Jn1iiiar-j- and July. A.
THIRD WEEK.
chart sliowing amplitude. to be mde during the m-eek.
FOURTH WEEK.
C'hnrt rrorX:-Higliest and lnaetit temperatures on record.
A c-1iwts showing extreme range of temperature, to be macle
during the week.
FIFTH WEEK.
f ' h r f tcvwX..--hniinal curves of temperntme a t selected Hta-
tions: coiiipariiig the sensoan1 msrch. of temperntiire in clif-
ferent, sections of the wuntry.
SIXTH WEEK. 4
(%nr.t iivrk.-Annual ciimes of temperature a t selected
Lwt it w. - (- 'cr i r s ~s if I#rrr)i m z t i ita n/i )i tin I cir rws.
s tdious.
SEVENTH WEEK.
I '11nrf unrX..-C'ontinnance of clnily mean temperature above
50' and below 3 2 O .
EIGHTH WEEK.
f%rt /I'fJd'.-A series of three charts ihstmting the pro- - gressive UlJVelnent of coli1 waves; remarks by the instructor.
(%urt W f J d . --dvernge annual precipitation in the United
St' .I t en.
Lt~c./irrr.-~~i~,.fx i!f pwroiIi/i~g iririds m r l i/icJro/tnira ~a n g ~s i r p i
/w i ~~i ;t (/t ;w i : h i w piw.~>itntiru/ is n i c w x t r r r d : rmrssiue precipita-
fifJH. rfr..
NINTH REEK.
TENTH WEEK.
Clllart u.nrX~.--Sensoiial prec-ipitation (four charts, the arerage
seasonal precipitation being entered for each State).