188 MON'I'ELY WEATHER REVIEW. MAY, 1905
in good condition and dolng well ; the prospects were for about a half
Crop Of aPPleh but were not very encouraging for chedes, Peaches, pears, and plums.-E. C. Yoae. by an e9cess of precipita-
tion, especially in the southern and central counties, and a deflciency of
temperature and sunshine. The continued wet weather retarded corn
Planting, but ~~8 8 generally favorable to the growth of grass and grain
crops. Frosts, more or less severe, occurred in the central and northern counties, and light snow was recorded on the 8th and 9th, but no material
damage resulted.- W. M . Wihoic.
Wyoming.-The month was unusually cool, the mean temperature for
the flret half of the month averaging about 60 per day below the normal.
The precipitation was heavy and well distributed. At the close of the
month, ranges were in excellent condition, and memk~ws gave Promise Of
a large crop of native hay. The cool, wet weather delayed seeding and
at the close of the month, gardens, grain, and alfalfa, while looking well,
were much later than usual.-'FV. '. Pa")7er.
whmin,-The weather was
SPECIAL ARTICLES.
STUDIES ON THE DIURNAL PERIODS IN THE LOWER STRATA OF THE ATMOSPHERE.
By Prof. FRANh H. BII.ELI)W.
1V.-THE DIURNAL PERIODS O F THE TERRESTRIAL MAGNETIC
FIELD AND THE APERIODIC DISTURBANCES.
TEE DIURNAL VARIATIONS OF THE TERRESTRIAL YAC+NETId FIELD.
In the years 1889-1891 I CoIuputed a series of hourly mag-
netic deflecting vectors for 30 stations, in polar coordinates,
8 = total vector, u = the horizontal component, ri = the angu-
lar altitude positive above the horizon, 19 = azimuthal angle
counted from the north point of the iuagnetic meridian
through the west = 9O0, south = 180°, east = 270°. These
were derived from the rectangular variations, -I H horizontal
force positive northward, J D declination positive westward,
d Ppositive zenithward, by means of a simple scale diagram
containing polar and rectangular coordinate systems a t the
same center. This presentation of the available data of obser-
vation included the diurnal variation of the magnetic field,
and also the variation from day to day eliminating the hourly
periodicity. The resulting tables are bulky ancl there has
been no opportunity to publish them in e.rtmso, but brief
summaries of the subject matter have appeared in several
places'. This work has aroused some criticaldiscnssion, but for
the greater part of an academic character which threw little
additional information upon the solution of the numerous dif-
cult problems in solar physics and cosmical meteorology that
are involved. It is quite evident that the authors of the com-
ments did not always have in mind the details or the minor
facts which must be accounted for in a final solution. I t is
easy to propose a vague general theory, but to bring i t down
to exact harmony with tlie many special peculiarities of the
varying magnetic field is no easy problem to resolve.
In 1889 Schuster ' published his solution for the diurnal
variation of the r~ettictrl force derived from four stations, and
ascribed to the assumed counterpart electric currents to a
sensitive state of the 11ppw atmosphere. I n 1897 von BezolclS
further discussed the subject as a continuation of the mine
data. In 1902 H. Fritsche ' computed the variations from
the difference data, J H, J P, J I', by means of Gaussian coef-
ficients, and likewise attributed the magnetic effects to sup-
posed electric currents in the upper atmosphere. I n his
paper of 1903, Adolph Schmidt' has adopted the method of
deflecting vectors, and in his other papers seems to favor an
electric current system in the high strata. Also, A. S. Steed
has worked out an elaborate system of upper air electric cur-
rents to account for the diurnal variation of the magnetic field.
Other writers, W. Sutherland, A. Nippoldt, W. van Bemme-
len, J. Liznar, Carlheim-C+yllenskiold, Ch. Chree, and L. 8.
Bauer seem to favor a solution of the same character.
I must confess that, aside from the entirely vague nature of
1 Weather Bureau Bulletin No. 2, 1898. Astrophysical .Journal, Octo- ber, 1893. American Journal of Science, December, 1891, August, 1895.
Weather Bureau Bulletin No. 21, 1898. Weather Bureau Annual Report, 1898-99, chapter 9. Eclipse Meteorology and Allied Problems, 1902,
chapter 4.
a The Diurnal Variation of Terrestrial Magnetism. A. Schuster, 1889. JZur Theorie des Erdniagnetismus.
H. Fritsche,
5 Eine Sammlung der wichtigsten Ergebnisse erdmagnetischer Beo-
'The Diurnal Variation of Terrestrial Magnetism. A. S . Steen, 1904.
'
W. von Bezold, 1897.
Die Tiigliche periode der Erdniagnetischen Elemente. 190a.
bachtungen. A. Schmidt, 1YO3.
this hypothesis, I have never been able to concede that it
contains the true germ of the solution of the problem. That
theory has received much additional popularity from the sup-
posed bombarclment of the upper strata of the earth's atmos-
phere l ~y the ions ejected from the solar surface and trans-
ported to the region of the earth's orbit by the mechanical
pressure of light, which were described as thereupon induc-
ing the required electric currents. It mas quite impossible to
understand how such a general action of currents in the upper
strata could produce the strongly localized effects observed
a t the surface of the earth, which so persistently follow the
meteorological elements both diurnally and annually. I have,
accordingly, (1) argued against the eificiency of these hypo-
thetical upper strata electric currents to produce the details
noted in the magnetic field, and I have (2) endeavored to show
that the general motions of the atmosphere and the cyclonic
and anticyclonic actions can not account for the observed
phenomena, taken the world over, as shown by my 30-inch
globe, model of 1893.
It is true that my own working hypothesis mas not complete
even in my own mind, and I have supposed there are steps in
the series of causes and effects that still require to be added.
My view was simply this, that the sun's electromagnetic or
radiant field of energy falling upon the atomic and molecular
constituents of the earth's atmosphere transformed them into
temporary magnetic states, by polarizing some of them it] situ,
that is, throughout the strata traversed by the solar energy.
These temporary magnets producecl a quasi magnetic field
which deflected the normal field as observed. The deflecting
forces were the products of the physical processes involved in
this action of the radiation upon the atoms and molecules of
the atmosphsre. This theory was constructed before the
phenomenon of ionization of the constituents of the terres-
trial atmosphere by solar radiation had been discovered, and,
of course, tliere was little scientific material to justify my hypo-
thesis a t that time. Furthermore, after the discovery of the
existence of positive ( +) ions ani1 negative (-) ions as constit-
uents of the atmosphere had been made, it still remained im-
possiiile to match the computed magnetic deflectiug forces with
the pressure and temperature period of diurnal variation as ob-
served a t the s t t r f m , of the earth. The search for conclusive
eviclence of the synchronism of magnetic vectors ancl surface
temperatures and pressures was always unsuccessful, but,
fortunately, this defect now seems to have been overcome by
the results of the computations summarized in this present
series of papers upon diurnal pressure and temperature waves
in the free air above the surface within one mile of the ground.
The desired synchronism seems to be so perfect as to leave
little ground for further doubt that the diurnal variation of the
earth's magnetic field is clue to the movement of the positive
(+) ions of electricity in the lower strata of the atmosphere in
streams that are induced and controlled chiefly by the diurnal
temperature waves that prevail in the lowest strata. I shall,
accordingly, consider this paper as a supplement to chapter 4
of Bulletin No. 31. The description of the magnetic rectors
there given is correct and in agreement with the systems
derived by later computers, but the process of producing
them, as now understood, is in accordauce with the facts
that have been worked out since that paper was written.
May, 1905. MONTHLY WEATHER R;EvIEW. 18 9
THE DIURNAL MAl3NETIC VECTORS AS THE EFFECT O F THE DIURNAL TEM-
PERATURE WAVES UPON THE REDISTRIBUTION OF THE POSITIVE ION3
IN THE LOWER STRATA O F THE ATMOSPHERE.
This subject can be best presented to the reader by making
a compilation of the vectors of the diurnal deflecting magnetic
forces and as computed for the same latitudes as those repre-
sented by the meteorological stations that have been used in the
comparison. For this purpose the following five stations have
been selected, as they are located in the North Ternperate Zone,
but in widely distributed longitudes: Washington, Paris, Vi-
enna, Tiflis, and Zi-ka-wei. Properly, Zi-ka-wei belongs part-
ly to the Temperate Zone belt and partly to the Tropic Zone
belt, magnetically considered, because i t is so far froin the
north maguetic pole as to be immersed in tlie tropical influence
during several months. Although this affects the azi~uut~h of
the hours during the night, I have not removed i t froin the
group of stations. The computed values of s, ~,~j i are extract,ed
from the tables described in chapter 4, of Bulletin No. 21, anti
an example is given in full for the months of February and
August in Table 10, “Hourly values of the polar coordinates,
s, a, ,9, a t five stations in the North Temperate Zone ”. The
mean values were computed for each element a t every hour,
and these are given for each month in Tnhle 8, “Vectors of the
diurnal magnetic deflecting forces”. x is in units of the fifth
decimal or 0.00001 of the unit of the C!. G. S. system; II = the
altitude angle positive above the horizon; ,j i = tlie azimuth
angle counted from the north through the west.
It is diflicult to exhibit the results of the Tables 10 and 11
on a diagram of only two dimensions, and I have inncle use in
my studies of globe models constructed of rubber balls with
pins for vectors, or else the large 30-inch globe model already
mentioned. However, a drawing has been made in fig. 55,
for latitudes
+30° to +60°”. The vector length s and the vertical angle IL
are plotted for each month, and the direction in azimuth ,j i is
laic1 down only for January and July, as the variation in this
element is not very great in the course of the year. We ~hould,
therefore, interpret the vectors as follows: The vector (s a )
should be understood to stand in the plane of the azimuth l Y ,
and make with it the angle u which is here given. Generally,
the vectors from 8 a. m. to 7 p. m. are directed toward the
south, and those from 8 p. m. to 7 a. in. toward the north.
As my purpose is to consider chiefly the relation of the streams
of + ions in the air to the vector (x u ) I have practically sacri-
ficed the azimuth in the diagram. On the globe model the
entire system is clearly displayed and it should be studied in
that way.
On fig. 55 there are seen to be four critical points in the
distribution of the diurnal vectors:
(1) The first point marks a sudden increase in the value of
the deflecting force s up to a maximum, and i t occurs in the
forenoon, ranging from about 8 a. m. in winter to 6 a. m. in the
summer. This is the hour a t which the azimuth @ shifts from
the northern to the southern quadrants. About two hours
later the vertical angle u passes through 0’ so that the vector
changes from below to above the horizon.
(2) The second point occurs a t 11-12 a. m. in winter and
10-11 a. m. in summer, where the azimuth 1 shifts from east
to west through the south, this being the well-known reversal
of the needle before noon. The d u e of s a t this point is a t
a slight minimum relative to its values earlier and later: this
midday minimum appears in nearly every month of the coni-
putation, but especially in summer.
(3) The third point occurs after the true midday maximum
of s, about 3 p. m., where the vector ( Y u) changes from above
to below the horizon, and a passes again through the zero
value of the angle. This point changes from about 2 p. m. in
winter to 4 p. m. in summer, thus moving in the opposite direc-
tion from midday to that indicated in the forenoon vectors.
Diurnal variation of the magnetic vectors s, a,
Frc:. 56.-The annual variation of the siirfai.e teinperature at Blue Hill.
(4) The fourth point is where the azimuth ,j. shifts from the
first and second quadrants to the third and fourth, and it
occurs at almiit 6-7 11. ni. in minter, but a t 7-8 p. m. in the
suiumer, a t the time of the setting of the sun. On fig. 55
these four special points in the system of diurnal vectors are
indicated by the four lines marked (l), (2), (3), (4), and by
190 MONTHLY WEATHER REMEW. MAY, 1906
their course they show that the entire action which produces
this magnetic disturbance of the normal field, contracts in
time toward noon in the winter, and spreads away from it in
the summer. This remarkable change in the location of the
turning points is related without doubt to a similar change in
the diurnal distribution of the temperature in the lower strata
of the atmosphere, which must be closely associated with the
magnetic variations.
In order to show how exactly these two phenomena syn-
chronize in time during the course of the year, I have trans-
ferred to fig. 56 from figs. 11-25 the surface temperatures its
observed a t Blue Hill, plotting them in the sense indicated by
the coordinatevalues. If the line (1) is drawn a t the locus of the
first active rise of temperature, a t about two hours later than
the minimum, the course is marked a t an earlier hour in sum-
mer than in winter. The line (2) is drawn a t about halfway
up the forenoon temperature slope; line (3) a t the maximum
of the temperature, and line (4) a t about halfway down the
afternoon temperature slope. On comparing the lines (l ), (a),
(3), (4) of fig. 56 with those of fig. 55, it is observed that the
annual curvature of the lines is generally so much in agree-
ment as to make it very probable that the magnetic field and
which itself has an entirely similar course to these in the
North Temperate Zone. Now, since i t is well known that this
diurnal temperature effect, is confined to the lower strata of
the atmosphere, within two miles of tlie surface, I have been
unable to concede that the diurnal magnetic variations can be
caused by electric currents in the y y w r stratn of the atmos-
phere, as assumed by Professor Schuster and other magneti-
cians, or that it can be caused by a bombardment of the u p p w
strata by the ions transported in the solar radiation, as sup-
posed by Professor Brrhenius and other physicists. While I
have been unable to relinquish my belief in a cause located in
the lower strata of the atmosphere, i t has been an exceedingly
difficult thing to discover a substantid physical cause that
will fix the exact location of a system of electric currents, or
other source of these magnet,ic vectors, in this region, and,
indeed, I had not been able to do so before arriving a t the
results of the kite observations as exhibited in the preceding
papers of this series. We have been led, a t length, very natu-
rally to see in the movement of the positive (+) ions in
streams, whose directions are determined by the temperature
distributions in the lower strata, a sufficient cause for the
diurnal variation of the electric potential field, and I shall now
show that this cause also accounts equally well for the diurnal
variation of the magnetic field in the North Temperate Zone.
The general relations may be represented schematically by
fig. 57, “The probable relations between the temperature waves,
the streams of positive (+) ions, and the magnetic vectors in
the lower strata of the atmosphere”. Let d represent the sur-
face of the earth which is charged with negative electricity.
A portion of this charge is derived from the ionized contents
of the atmosphere, due to the action of the short waves of the
solar radiation upon the constituents of the atmosphere, espe-
cially the aqueous rapor located within an arch spanning the
Tropics. Another portion of the negative charge is probably
derived from inside the earth, and is due to the excess of dif-
ferential circulation of the negative (-) ions over the positive
(+) ions in the atomic conflict a t the prevailing high temper-
ature and pressure, by which more of the negative electric
ions are detached from the atoms and in circulating are polar-
ized by the earth’s rotation SO as to produce the internal mag-
netism of the earth and an electrostatic charge a t the surface.
If the negative ions rotate more rapidly than the positive, as
with the velocity of light, the deflecting force due to the earth’s
rotation must be large, and tend to cause these ions to move
in planes perpendicular to the axis of rotation. This will cause
an internal magnetic field directed from north to south.
the temperature are both direct eEects of the solar radi a t‘ 1011,
The surface charge of negative ions is supposed to rest quite
steadily on the earth, or within it, while the positive (+) ions
of the atmosphere rise and fall from one stratum to another ac-
cording to the change in the air temperatures, as i f the posi-
tive (+ ) ions had an sanity for certain temperatures, which
they seek through vertical and horizontal motions. Let B
represent the ordinary surface temperature wave, with which
it has never been possible to associate the diurnal magnetic
vectors. Let C represent the semidiurual temperature wave
in the lower strata of the atmosphere as integrated in the di-
urnal convections, generally within half a mile of the ground.
The maximum temperature occurs a t 3 a. n ~. ancl 3 11. m., and
the minimum a t 8 a. m. ancl H p. m., both of these subject to
the annual variation in time already indicated. Let D repre-
sent the probable streams of positive ions. directed vertically
upward a t 3 a. m. and 3 p. m., but downward at 8 a. m. and 8
p. m. It should be observed that at 3 a. m. tlie vertical up-
ward current of the semidiurnal wave is really neutralized by
the downward current of the surface wave, aud that during
the night hours we should have sinal1 resiclunl inotioiis on the
whole of a downward direction; that. a t ti a. in. ant1 8 11. m.
the downward semidiurnal waves prevail became the surface
temperatures are nearly normal to the clay and the convectional
currents are producing lower temperatm-es; and, that, a t 3
p. m. both the cliurnsl and the semicliurnal mares unite in a com-
mon upward vertical component. We may assume, then, that
the positive ions descend vertically a t 8 a. 111. and 8 p. m., but
ascend vertically a t 3 p. in. The accompanying adjacent
streams on the preceding side of tlie 8 a. ni. vertical, bend to the
left in the early morning hours, but to the right after that hour.
These latter naturally recurve, becomiug horizontal a t 10
a. In. to 11 a. m. in order to ascend in the warin midday current.
A t t.i p. m. the positive (+) ions first clescenfl, recurve by be-
coming horizontal a t 6 p. ~n . to 7 p. m. ancl ascend in the warm
afternoon current, while those farther to the right slowly
descend throughout the night. Let E represent the corres-
ponding magnetic deflecting forces, wliioh are generally found
t,o be a t right-angles to the electric streams as thus located
ancl always directed in the same sense.
ELectric
current .
This remarkably consistent corelation of cause and effect
throughout the diurnal fields is greatly in favor of the theory
here ascribed. Finally, it should be remembered that this entire
temperature system is moving as indicated by the arrow F on
the diagram from right to left, ancl that the warm wave is con-
tinuously intruding upon the cool regions to the left of it.
If the positive (+) ions seek to avoid an excess of warm tem-
perature by streaming from low levels during the hours from
10-11 a. ni. to 6-7 p. m. into the higher levels with a maxi-
mum a t 3 p. m., that is generally by moving upward in the
warm current, the effect is to leave the positive (+) ions in
the higher strata throughout the evening and night hours.
There is not so much a continuous electric circuit, with the
same velocity in all parts of i t as in A conductor. but rather an
alternate rise and fall of the electric charges a t different parts
of the day, that is a falling by night and a rising by clay,
somewhat as is indicated in the diagrams. The westward
lateral movement of the diurnal system probably tends to keep
Plate I.
. 55.-Diurnal variation
f
1
1
I
I
I
I
I I I
I
i
I magnetic vectors. 8, a, p 3
I + 30° to + 609 8, a, for each month, /3, for January E
br 1
J
s
FIG. 58.-The streams of + ions causing the diurnal magneticvectors in the Polar, Temperate, and Tropical zones of the earth.
FIQ. 59,-The general disturbance : Magnetic vectors directed south- ward and caused by a flow of + ions from south to north in the air.
FIG. 60.-The general disturbance : Magnetic vectors directed north-
ward and caused by a flow of + ions from north to south in the air.
Plate 11. 34
FIG. 5'7.-Probable relations between the temperature waves, the streams of + ions, and the magnetic vectors in the lower strata of the atmos-
phere.
A = negatively charged surface of earth. B = the surface temperature wave.
C = the semidiurnal temperature wave at the height of 400-600 meters.
= the probable stream lines of t h e positive ions, as moving charges.
E = the correspbnding magnetic vectors.
F r direction of motion of the system.
MAY, 1906. MONTHLY WATHER REVIEW. 191
wider open the streams of ions before noon, at 10 a. m. to 1
p. m., and to make them closer together at about 6 p. m. to 7
p. m. At the same time, as already explained, there is pro-
duced the increase of the atmospheric electric potential
gradient to a maximum at 8 a. m. and 8 p. m. by the approach
of the positive (+) ions to the negative (-) ions lying at the
surface, also, an increase in the rate of dissipation of the two
kinds of charges by the more immediate mixture and contact.
It is not necessary to remark that we do not suppose that the
positive (+) ions and the negative (-) ions are separated
from each other so exclusively as is here indicated, but only
that there is an excess of the positive (+) ions in the strata
above the ground, and an excess of the negative (--) ions
near the surface. It may be noted that the conflict in clirec-
tion from 4 p. m. to 9 p. m. between the convection air cur-
rents and between the streams of the ions, one being upvarcl
and the other downward, is very favorable to the production
of thunderstorms.
THE DIURNAL MAGNETIC VECTORS I N THE POLAR, TEMPERATE, AND
TROPICAL ZONES C )F THE EARTH.
Similar considerations applied to the magnetic hourly vec-
tors which have been computed in the other zones of the
earth, and described in chapter 4 of Bulletin No. 31, lead to
the following conclusions, illustrated schematically in fig. 55.
The normal magnetic field of the earth, positive in the South-
ern Hemisphere, has the horizontal component directed north-
ward, while the vertical is upward in the Southern Hemisphere,
but downward in the Northern Hemisphere. The downward
positive (+) ion stream repels the north end of the magnet
eastward in the North Temperate Zone, but westward in the
South Temperate Zone ; the upward positive (+) ion stream
works in the opposite sense. Hence, the descending positive (+ )
ion stream from 7 p. m. to 11 a.m. (fig. 5 7 ) in the Northern Hem-
isphere directs the north end of the needle eastward, but in the
Southern Hemisphere, westward. The ascending stream di-
rects it westward in the Northern Hemisphere and eastward in
the Southern Hemisphere. The same diurnal temperature
waves, therefore, produce the required opposite magnetic
effect in the respective hemispheres. I n the Tropical Zone the
vectors on the sunward side are directed northward for the
ascending positive (+) ion streams, and southward in the
night, 4 p. m. to 8 a. m. for the descending streams. I n the
Polar Zone the outspreading magnetic sheets on the morning
side of the pole imply a descending stream of ions which is
directed from left to right, or west to east: and on the afternoon
side the ascending and concentrating magnetic vector sheeth
imply an outflowing system of positive (+) ions which ascend
into regions about the surface. Generally, these magnetic
vectors in the three zones require electric currents directed
from west to east in the Polar Zone athwart the direction of
the lines of the solar radiation: those in the Temperate Zcnes
require lines nearly in planes from north to south, and also
athwart the solar radiation field; finally those in the Tropicx
require positive (+) ion streams parallel to the direction of
the same radiation. These three rectangular systems of elec-
tric currents evidently form those types of couples, exactly
the counterparts of the three sets of magnetic couples which
were described in the same chapter of Bulletin No. 21. For
some reason the positive (+) ions seem to prefer to travel at
right angles or else parallel to the lines of the electroniagnetic
radiation, even when they are passing along paths which are
rendered fsvorable by the temperature conditions already
esisting in the lower strata of the atmosphere. It is evident
that these prevailing conditions imply a possible solution of
several important physical questions in electricity and mag-
netism in the earth's atmosphere, when suitable observations
have been acquired. The theory which I advanced to account
for the observed diurnal magnetic vectors in my preliminary
papers is now much more satisfactorily stated, by such an
26-2
addition to its terms as haa been drawn from the process
depending upon the ionization and temperature effects of
the solar radiation in the lower atmosphere. Apart from
clearness of exposition, i t seems to me that the view there ad-
vanced, namely, that the magnetic rectors are products of the
electromagnetic radiation as the result of its action on the
atoms of the atmosphere is substantially strengthened. The
entire subject, though intellectually more satisfactory, is also
much more difficult to handle scientifically, because the inter-
mediate steps involved in the action of the ions in relation to
the temperature, must be worked out by observations in the
lower strata of the atmosphere, and such data are very difficult
to acquire in a reliable form.
THE SYSTEM O F DdILY MAQNETIC VECTORS, A9 DISTINt'T FROM THE
HOURLY VEPTOHS.
Besides the system of hourly deflecting magnetic forces
described in chapter 4, Bulletin No. 21, I also worked out a
second vector system, which gives the vectors day by day,
disturbing the normal magnetic field in the day intervals,
taking the several successive groups of 24 hours in succes-
sion. These vectors are summarizecl in chapter 3, of the
same bulletin, and it was there sliown that they consist of
vectors acting nearly in the planes of the magnetic meridians
directed northward or southward as the case may be. Since
the entire magnetic field of the earth is involved in these dis-
turbances, which often run three or four clays in the same
direction, before reversal to the other side of the normal oc-
curs, it is necessary to seek for a general causeinstead of one
that is distinctly local. The mere temperature effects of
meteorological circulation can not be the dominant cause, be-
cause the two systems of conditions do not synchronize. It
was also shown that this general magnetic field, taking the
annual values of the vector P, does vary in parallel with that
of the solar field as shown by the frequent number of spots,
facule, and prominences. According to that interpretation of
several phenomena which was adopted and which is probably
pliysically correct, the sun was found to be magnetized.
The solar action and the magnetic terrestrial effect undoubt-
edly synchronize in the long run, but there has been great
difficulty in assigning SO large physical fluctuations to the
sun itself as seem to be required to account for the observed
magnetic conditions at the earth. I t has seemed to me nec-
essary to assign to the direct magnetic field of the sun at
least the function of setting in operation such terrestrial forces
in the earth's atmosphere as should make up between them
the required magnetic eficiency. Just what that terrestrial
proc%ss is in fact, there has been trouble in detecting, and in
assigning to i t a sufficiently natural i ~~d u s ~~]wrundf. The vio-
lent fluctuations of the magnetic field could hardly be ascribed
exclusively to variations in the normal solar electroinagnetic
radiations, for two reasons: (1) The sun woulcl be a variable
star of such a convulsive type as to be inconsistent with the
comparatively steady flow of heat which the earth receives
from it. Nor can this view be suitably modified by adcling
smh a bombardment of solar ions as Arrhenius has suggested,
because their possible eficiency is not nearly great enough to
match the great magnetic fluctuations which are continually
being recorded. (2) The vector system pertaining to these
daily clisturbances is entirely different in type from that
found in the hourly variations. Indeed, I showed by the
computation on Table 15, page 76, Bulletin No. 21, that in the
case of strong disturbances the ordinary hourly disturbing
vectors (fig. 58) are transformed hour by hour into a system
of vectors like the general type (fig. 59), thus proving that
these two phenomena have essentially different originating
causes, so far as their effects on the observed magnetic vectors
are concerned. I have not failed to recognize the difficulties
of my own theuries in this problem, nor have I discovered in
other papers a solution which seemed in anywise competent
192 MONTHLY WEATHER REVIEW. MAY, 1906
to account for all the conditions a t the solar end and a t the
terrestrial end of the line of cause and effect. The following
view is, therefore, suggested with the impression that it forms
an excellent working hypothesis for further examination.
Taking such a group of lines of force as are to be found on
charts 17, 18, of Bulletin No. 21, which shows that the mag-
netic force is subject to world-wide variations of the same type
on the same dates, it is evident that the normal field of the
entire earth is for a while disturbed by a set of vectors point-
ing southward, and again by a set of vectors pointing north-
ward. The mean vectors of this system a t the several latitudes
of the earth were computed, and they are plotted on chart 10
of Bulletin No. 21. They have longer vectors in the polar re-
gions and in latitudes 20" to 40" than in the latitudes 40' to
60' and 0" to 20'. I have transferred them to fig. 59, which
shows the magnetic vectors s directed southward ani1 to fig.
60, which shows them pointing northward, of course referring
to two seperate occasions. This alternate action, or reversal
of the entire system of magnetic deflecting forces, is the phe-
nomenon to be explainecl.
By extending our notion of streams of positive (+) ions
moving from point to point in the atmosphere, we have merely
to suppose that on certain provocations the positive (+) ions
move from one hemisphere to the other in the atmosphere, re-
turning again through the outer shell of tlie earth, as indicated
on the diagrams. For a southward directed magnetic system,
the positive (+) ions stream from the Southern Hemisphere
along the arches in the atmosphere niost favorable to their
movement, whether due to temperature and vapor conditions,
or to special ionization and conductivity functions. This flow
of the positive (+ ) ions induces the magnetic vectors a t the
surface, and the positive (+ ) ions stream back from the North-
ern Hemisphere to the Southern through the crust of the
earth, thus causing the earth currents which always accom-
pany agitation of the normal magnetic field. For a northward
directed system of vectors the positive (+) ions stream from the
Northern to the Southern Hemisphere in the air, and return
thence through the outer shell of the earth. The magnitude
of the disturbance of the normal magnetic field depends upon
the intensity of the stream of ions flowing along these paths.
and that is a function of tlie number of the ions and the veloc-
ity of their motion,
I = e ( n+ v+ + 1 1 - P -),
where e is tlie charge of electricity of each ion, /i + and tL-, the
number of the positive (+ ) ions and the negative (- ) ions, a i d
v+ and u-, the velocity of the same. The simultaneous occur-
rence of the aurora in both hemispheres is evidence of the ac-
tion of the ions which, in traversing the gases of the atmos-
phere in the low or the high strata, procluce the observed
luminous effects as phosphorescence or fluorescence. It should
be observed that the hourly location of the aurora frequeuoy
occurs in the regions marked out on fig. 58 by the streains of
ions, that is in the earJy morning and the early evening hours,
since there is a region of minimum of frequency stretching
from 11 a. m. across the polar region to 11 p. m.
This simple explanation of the long series of interrelatecl
phenomena, which has so long escaped a natural correlation,
has much to commend it to careful consideration. The quan-
titative determination of the number of ions involved, and
their velocity of motion in the circuit from one hemisphere to
the other, will require much exact research work upon t,he
various functions involved in the physical processes.
'
THE DISTRIBUTION OF THE APERIODIC! DISTURBANCES.
It has been very dificult to assign to the observed disturb-
ances of the magnetic field, that is to the large variations of a
spasmodic character, like temporary storms, which occur in the
normal field, a satisfactory explanation. The attempt to ascribe
the physical cause esclusively to variations of the solar action
in situ, that is in the sun itself. as for example, the sun spots,
or the prominences, is attended with unusual troubles of a
physical nature. The following analysis may tend to throw
some light on the subject.
The clisturbances which occurred a t Washington, D. C.,
during the pears 1859, 1890, and 1S91 were subjected to an
analysis similar to that used in other connections, by which the
polar disturbance vectors n, 8, (1, ,3, were computed for each
half hour of those days on which the traces were decidedly
agitated, as 1889, February 28, 29, 3Iarch 5, 6, 17. and so on
throughout the three years. The purpose was to fix their
daily tlistribution as a diurnal period, and the direction from
which they come upon the normal field. The mean vector for
the 24 hours was,
s = 245 for $between 315" and 45' that is north;
315 '' ,? '( &jn 315O '( west;
30s p '' 325" 315" '' east.
33:? " ,s " 135" '( 235' I C HOllth.
Hence, the south quadrant receives the strongest impulse,
while the east and west quadrants are inore disturbed than
the north quadrant. Fig. 61 contains the curve of relative
numbers showing the diurnal frequency of the clisturbance,
the innxima being a t 12 to 1 p. in. and 12 to 1 a. m. Coinpar-
ing with fig. 57, i t is seen that tliese maxima agree with the
position of the niasima of intensity of the ascending stream
of positive (+) ions, as determined by the temperature curve
of the lower strata, that is the one located a few hundred
meters above the surface. We may infer that one source of
the magnetic disturbances is in the t,emperature waves which
induce the movement of the streams of positive (+) ions,
especially in a vertical direction. Hence, these hourly magnetic
disturbances are specifically meteorological phenomena occur-
ing in the lower strata of the atmosphere, and are the products
of the snlar radiation producecl through the intermediate
agency of the ionization and teniperature waves.
FIG. Gl.-DistrllJi~tiou of the honrlj maxnetic. dihtnrhances at Wadi-
ington, D. C!., in the years 18S9. 1890, 1891.
There is yet another cause for the other type of great mag-
netic storms which endure for several clays, as elistinct from
those lasting a few hours, and cause the excessive variations
in the diurnal field. In working up my data into the 26.68-
clay period, and deducing the resulting mean magnetic curve,
as shown on chart 21, Bulletin No. 21, or by the upper curve
on fig. 62, I excluded the large iuagnetic disturbances be-
yond a certain amplitude, for the sake of obtaining the normal
structural magnetic impulse clue to the rotation of the sun on
its axis, if any such exists. The curve mentioned has been
found to reappear generally, though a t the expense of much
waste of material in computing, to eliminate the other kinds of
irregularities by mutual self destruction, in nearly all the solar
and terrestrial phenomena. It, therefore, seems to point to an
organized mass in the sun due to a highly viscous mass hav-
ing great rigidity a t immense pressure, or to a definite organic
circulation. Similarly I have countecl out the dates of occur-
rences of the magnetic disturbances recorclecl a t Greenwich,
1882-1903, as collected by Mr. Maunder in his paper,
MAY, 1906. MONTHLY WEATHER REVIEW. 193
Monthly Notices R. A. S., November, 1904, and entered them
in a table based upon the 26.68-day ephemeris. The result is
shown also in fig. 62, and i t seems to imply that the 26.68-day
period is a t the basis of the distribution of the great magnetic
storms, rather than the 27.35-day period, which is the average
in the sun-spot belt.
FIG. 62.-Distribution of the great mapietic di4urhances in the
26.68-day Iieriorl (Maunder’s data).
In Terrestrial Magnetism, Vol. S, 1). 12, March, 1905, C’h.
Chree gives a table which shows the number of great magnetic
storms, using Maunder’s data, that commenced on the severnl
hours of the day. These numbers are plotted on fig. 63 wliich
shows that there is a distinct masiinum at 1. p. m. The num-
bers are distributed without distinction as to hours during
the night and early morning, but at 10 a. ni. a pronounced in-
crease in the number per hour set in which culminates a t
1 p. m. and falls off gradually to X 11. m. On comparing this
curve, fig. 63, with that of the diurnal disturbance curve, fig.
61, it is seen that the principal masima agree at the same
hour. The inference is that the great disturbances lasting
aeveral days, as well as disturbances which are limited to a few
hours in duration, each tend to concentrate about the 1 p. m.
hour when the nscensional current of the positive (+) ions is
strongest. From figs. G2 and 63 it is quite certain that the
great disturbances have two terms entering into their compo-
sition, one belonging to the sun’s atmosphere and the other to
the earth’s atmosphere. The final solution of this problem is
evidently dependent upon a knowledge of many terms other
than a mere enumeration and matching of the number of the
sun spots and prominences with the magnetic traces.
FIa. 63.-Number of great magnetic distiirbarlct~h coiniiienciiig at the
several hours (C. Chree’s Table, Terr. Mag. Vol. S, No. 1, 1’. 14 I.
The physical impulses from the sun to the earth niny come
in two ways, (1) by the radial path of the solar radiation, ancl
(2) by the curved path of a direct magnetic polar field. Either
of these may operate separately, or both of thenrinny work
together, to alter the normal balance among the positive (+)
ions in the earth’s atmosphere, and thus start them flowing in
the paths indicated on figs. 58,59, southward or northward as
the case may be. As a matter of fact, the great magnetic
storms lasting two or three days are found to require a cleflect-
ing vector system pointing southward, so that the positive
(+) ions flow northward in the air strata. They may continue
to flow as long as the solar impulse, whether of radiation or
of direct magnetic field, is passing the position of the earth
in its orbit. On this view the strain is removed from the origi-
nal theory that the sun can not by direct action as a magnetic
sphere influence the earth to the full extent required by the
observations, because only a part of the energy traverses the
cosmical space from the sun to the earth, while the remainder
is simply due to the streams of ions in the atmosphere flowing
as adjustment currents.
Enough has been shown, I believe, to make i t clear, (1) that
the variations of the terrest)rial magnetic field are distinctly
iiieteorological effects, and should properly be examined by
the meteorologist rather than by the geophysicist; (2) that
this interaction of the electric, magnetic, and teniperature
effects, whether at t,he sun or at the earth, constitutes one of
the most fascinating problems open to scientific research. If
the production of ions by solar action, their distribution stati-
cally aucl dynamically under the influence of atmospheric pres-
sure, temperature, and vapor contents can be thoroughly
worked out, the result will be to raise meteorology to a prac-
tical science of the highest rank. The numerous cross con-
nections between radiation, whether variable or constant, the
ionization in the s o l ~r and in the terrestrial envelopes, the
consequent circulation of the solar mass and of the earth’s
atmosphere, the resulting weather and climates, make up E
series of research problems of much clifliculty, ancl yet of such
promising value to all men as to justify a much greater activ-
ity on the part of astrophysicists and meteorologists than has
been given to the subject of ccismical meteorology in the past.
I n chapter 9, of the International C!loud Report, some ac-
count was given of the relation between the distribution of
the pressure waves and the magnetic field vectors in the polar
regions, as well as in tlie Tropics and middle latitudes. It
was shown that the diurnal wave ill the Tropics and the tem-
perate zones advances over the earth as a long double wave
extencling from latitudes +GOo to --GOo, but that in the Polar
Zone a single wave of masiinuni crosses the poles with a phase
about 90” clif-ferent froin either of the inasimum pressure
waves in lower latitudes. It appears that the distribution of
the magnetic vectors is closely associated with this single
pressure wave in the Arctic regions, but I could give no suit-
able explanation of this sudden transition from the double to
the &ingle wave at the latitude 60’. It now appears that the
semitliurnal waves are clue to temperature eiTects and convec-
tion currents in the lower strata, as within GOO meters of the
surface, and that above them from 600 meters to 3000 meters
there exists n, single temperature wave, located halfway be-
tween them, which likewise is produced as the result of the
teniperature distribution in the lower strata. Now, since in
the temperate zones, the double temperature waves exist at
low levels and the single temperature wave at high levels, it
is quite likely that this single wave descends to the surface in
the Polar Zone, and induces the single pressure wave which
acconipanies it. Thus, tlie single temperature and pressure
waves rest on the surface in the polar zones, but pass over-
head as an arch in the temperate and the tropical zones,
higher in the Tropics than in the micldle latitudes. This is
quite similar to the clistribution of the aqueous vapor con-
tents in an arch, and it is probable that the positive (+) ions
travel along this high pressure arch through the earth’s at-
niospliere rather than by any other route. The vectors of
figs. 59, 60 shorn that long vectors occur in the Polar Zone,
and in tlie latitucles between the eastward drift of the tem-
perate zones and the westward drift of the Tropics, that is to
say, in the belts of the earth where the high pressure distri-
lJutions come to the surface. The cloud belts of the Temper-
ate Zone, latitudes -10’ to 50°, and near the equator, +loo to
-loo, apparently impede the circulation of the streams of
ions and so produce short disturbing vectors in those belts.
THE C’OMPONENTX OF THE DIURNAL WIND VELOCITY.
194 MONTHLY WEATHER REVIEW. ,Mm, 1905
2 ...... 3 ......
A ,.....
s ..... 6......
a . .. . . . g......
10 ......
I? ......
11 ......
TABLE 11.- Vectors of the diurnal magnetic deficting forces.
p aziniuth mgle, R. =OO, W. =goo, H. = 180°, E. = 270.
g iu teriiia ~d0.00001 C . G. S. unit.
a vertical nnglr, pamitire to zenith.
13
8
R
5
5
5
G
i
1
-
6
Finally, by comparing the diurnal wind vectors, as deduced
from the surface and the free air observations, i t will be seen
that they harmonize closely with the other results of this
analysis. I may remark in conclusion, that there seems to be
little need to adopt the theory of Arrhenius, that the mag-
netic disturbances are due to a bombardment of the solar
ions traversing the space between the earth and the sun, be-
cause the disturbance of the normal temperature, or the
normal electrical field and magnetic field by radiation effects,
or by the direct magnetic effects, is suficient to set up n
counterbalancing circulation of the ions. The entire system
of the sun and the earth constitute tl delicately balanced wire-
less telegraphic system, and the ions may be regarded as sen-
sitive coherers, which respond to every impulse tending to
disturb the equilibrium. It should be especially observed
that the variation of the magnetic field n t the surface most
effectively and simply integrates the entire eficient energy
expended in these several types of force. If the temperature
waves in the lower strata disturb the ions, and these induce
the magnetic deflecting forces. then, in the inverse order, the
magnetic force a t the ground measures the nature of the tem-
perature wave passing overhead. In this aspect of the case
the magnet can be made to register the temperatures in t,he
lower strata of the air a t least indirectly, and probably very
efficiently, when the function becomes fully understood, and
in this sense a magnetic observatory is essential to the prog-
ress of the higher meteorology.
TABLE 10.-Hourly aaliiea of the polar conrtlinntes 8, a , /3 at 3z.e stations
in the North Tenipt.rccte Zone.
W. = Waehiogton. F. = Pariq. V. = Virnua. T = Tifli-. Z =Z~-ka-nt.i.
FEBRC AKT.
a B I
8 . .. .. .
'J......
10.. . . . . 11 ...... 12.. . . . .
-
~
S
~
9
Y
Y
8
s
10
12
17
21
2IJ ??
27
28
29
?I
I?
8
f
6
7
8
J
9
9
I
-
~
Y
~
S
7
b
0 9
lti
23
"Y
X I
27
24
2.i
29
34
32
,
11 ...
'P.. 2..
3...
4... l... 6... 7...
8 ... 9. .. IO.. . 11.. . 12.. .
3 11 34 10 12 15 1 2 3 t34 +35 +61 +28 +34 228 144 200 142 333 20:)
12 16 40 16 15 20 +Z" +"3 t 4 l J +23 4-26 153 IOfi 160 100 8 IO3
16 15 31 16 16 19 +13 +12 +I3 +11 + i +l I 100 94 124 91 $3 59
16 10 21 14 12 15 + 9 0 - 3 - 4 + 5 t 1 87 96 111 116 .W 89
10 7 15 11 7 10 +I2 -16 -16 -15 -4.5 -16 81 I l i 102 128 36 93 6 4 10 10 5 7 +?3 -35 -29 -23 -90 -31 88 90 122 129 0
1
85
6 4 6 9 6 fi +I X -57 -45 -36 -4.5 -33 91 I)o 75 lfi4 140 100
16 19 31 18 19 21 +iii t i 5 rfi +27 t i 9 t i 8 128 93 145 yo 27 97
10 5 i
6
9 7
7 s
3 8
7 8
-IO -I7 -13 -21 -18
+ 5 -I3 -17 -17 -20
t 8 -15 -18 -13 -26 +I2 -~ G -12 -17 -33 +I9 -11 -1s -3' -30 -2 -14 -20 -32 -33 - S -15 -22 -I8 -25
- 1 -11 -20 -I6 -16
-1 -4 -21 -'1 -in
-16 -14 -13
-11
-12
-I8
-18 -I3 -4
7 ......
8 ....
!) ......
I l l ...... 11 ......
l ......
3 ......
.I..... . 5 ...... G ......
7 ......
a ,..... g ......
121' ....
12
22 -12 25 - 8 25 +a 21 +"O
29 +27
35 +I7 34 +I3
51) +I
18 -10
10 -34
7 -41
7 -50 7 -43
9 --52
8 -26
+11 t P O +25 +I ; + 8
+ 1 t10 +I5 +I4 + 4 -5 -6 +I 3 +S -3 -5 -33 -14 0 -18 -43 -72 -63 -39 -15 -46 -?2 -45 -i 5 -Id
-40 -4s -L% 4 s -1s
-21 -33 -20 -63 + 3 -26 -29 -17 -45 0 -31 -22 -20 -31 -10
-17 -20 -17 -27 -20 -10 -17 -13 -21 -18
+I6
+ Y
+2 -19
-46
-51
-36
-27
-23
-23 -3 -16
~-
-
B
290
3 5
294 2%
2x6
235 2h9 234 2.59
24 1
?? 1 161
94
84
R I
78
84
100
140
131 285 289
28 4
283
3 0
-
-
B
hlarrli. April.
~
a
-
B
~
265
2SY
271
"79
296
305 312
2s"
2!17 292
257
PU9
!I7
s9
89 9:;
R5
1211
900
26s
2.54
"fi3
261)
265
105
a B
~-
ss5
2hh
"3 I
304
?!IS
381 3 9
311 2ih
266
24U
182
103 95 h9
R6
94
134
122
123
214
271;
2fi9 276 285
~
Y
7
8
8 9 9
10
14
21
27
26
23 26
35
40
3fi
25
16 11 11
Y
11
9 9
6 7
-
X
9
6
6 5
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7 9 12
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1 5
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IO 7
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8
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8 7
8 10 16 25
30 30 26 22
25
31
35 34
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1Y
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9 9 1 I)
9
8
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a
0
-13
-I4
-9
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-3 -2
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+ 20
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t l l
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-
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a
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-14
- I4
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-I 1
+1
+I9 +I2
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-30
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-30
0
+3 I-lfi
+I9 t 23
+I 4
$:k
+r;
+I 0 121 t 24
i 20
+!' -
-2 1
-36
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-47
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-I4
-9
7
-3
-
D
-11
-19
-14
-10
-9
-9 -1 1
-21
-17 -2
t 14 i 35
+R4
-1 su
+I 4 -
-14
-31 --"s
-3 1
- 2Y
-28
-19
-1s
-11
12:i ...., r,
l ...... i -1 2 ......1 4
3 ...... 4
2511
385 296
3-13 363
3 73 365
354
32 I
298
2 l i
176 I30 101
93 99
115
131
1211
207
2lX
260
256 256
258
Juue. August.
~
s a
Joly.
B a B
~~~
0
-24 2 i 8
-5 J 2881 -15 2x2
-10 291 -12 2ps
-14 2Sli
-11 275
- 5 2R5 0 252
4 7 225
-I
0 0
I;
7 7
7 9
14
22 26
25
23
19
24
31)
35 32 23
14
10
9
s 8
I
8
7
6
-31
-36
-20
-1Y
-1 i
-16 -13
-9
-4
+7
+ 34
+4.1
+ 33
+ 21
+13
+" -15
-45
-31
-48
-34
-3 I
-27
-2s
-31
?i s
281
302
302 296
284
276
263
256 2%
I98
I06
H i
S I
73
78
81
94
112
166 256 294
277 282
278
4 -16 292 S -14 329
s -13 321 10 -11 315
11 -12 300
24 15 -19 -18 207 ?hO
31 -I3 267 :X? - 9 226
27 - 1 227
27 +31 128
32 + 9 80
21 +?9 162
37 x7 +23 +I6 98 YS
21 I !? 7.5
1" a . . . . 1 ..... 2. .. .. . 3 ......
4. .. .. . s ...... 6 ..___
Y ...... 9.. . .. .I
1 . . . . . .
i n . .. . . .
1s p ... .
11 ......
l ......
2 ..... 3 ......
4 ......
5 ..... ti. .. . . . 7......
-22 302
-IS 317
-25 295
-20 "90
-14 2i9
-10 265
- 6 251
+ 5 233 +?O 20s
+85 139
+30 10.5 +21 s9
+I4
+29 2JM +36 139 +30 100
+23 Sl
+14 SY
+ 1 .SI
-12 80
-36 $7
-53 7fi
-49 14s
4 6 %20
-38 310
-a: 3M
-27 287 -24 2iY
26 + 4 81
17 -10 78
10 -32 87
'J -50 111
10 -38 96
9 -33 312 9 --30 2911
9 --"' "92
Y -27 2i7
h -25 372
~~
Novemher.
~-
~~
11 L19 is 9 -46 86
1c -SI 63
1U -26 45
I.. 8.. .
10 -27 314
!I -23 320
9 -23 256
10 -20 274
Y -I6 292
Decemher. Octoher
3 5
6 7
8
10
4
6
10
If 13
9
, ~~
+ 23 - 23
-26
-25 -31
-28
4 5 -2 1
-18
-8
-I
-5
- 65
4 5 -29
-20 -13 -12
-45
-4 5 -30
-40
S O -12
-22
0
-6 -8
-I8 -8
~~
-31 -27 -22
- '20
-13
-m
~~
245
279 256 271
286 272
..
295 215
2XS
286 "78
276
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3x3 306
304
303
309
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217
210
254
260 270
"97
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160
191 167
1 72 163
180
.9 a B
-
272
306
319 313
333 344 341 310 274
247
214
163 107
93
8!1
67
110 130
156 235
2 72 272
2% 289
372
-
8 a B
-
268 3'5
286 322
331 365 347 3 s 319 "SI
214
1 i 4
!llj
94
Y9 115 116
142
116
195 256
258 21;5 264
263
-
323 333 322
317
320 311 300 274 2 32
226 1%
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92 82
77
811
159
148
168 262
2% 290
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3h5
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8 0 7 +3
8 -1
8 +1 9 0
10 - 7 14 -16
2n -15 22 - I)
24 +I5 24 +26 29 +?4
32 +I 6
26 + !I
18 - G
9 -34 8 -36 9 -43
8 -51
9 -36 11 --2Y
11 -20
11 -15
10 -10
0
9 +?
7 t 6
6 +23 5 1 2 3
6 +16 7 +I7 10 - 4
10 - 6
10 -12
10 +I 4
12 +so
19 +I O
1.7 - 6
13 -20
11 -35 9 -so 8 -35
7 -36 (1 -2"
11 -19 11 -18
9 -6
9 +2
"2 IS +25 +IS
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6 +10 252 7 +I6 256
3 +26 277
3 +28 316 4 +14 362
6 +IO 364 7 + 3 369
9 + 4 359 11 - 3 349
9 + I( 311 7 +22 238 11 +27 175
14 +18 121
14 0 111
11 -1 109
8 -18 108
Y -20 133 6 -24 126
4 -24 128
4 -27 327 5 -19 243
6 -15 250 7 -10 248
7 +S 254 ti +IO 252
I 0
AUGUST.
a ..... . 10 - .
5 . ... 18 -10 4 .....1 12 -9 360 445 34 1 352 292
303 B 5 272
151
?2S 1 s:j 155
112
93
Sl
71
51
3s
14
350 348
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340
348
360
31s 319
320
305 2%
279 266 252 232
218 171
153
96
97
97
86
80
4.5
315 2-13
:+:+I
319
815
315
316
32s
315
29i
300 297
298 280 279
236
209
177 157 11s
101
S I
81
85
90 115
346
350
34G
388
333
328
320 307
306 294
294
287 270
254
240
S I 7
1%
114
87 77
71
72
74
$11)
150
90 360
3 L3
32
508
320
135
360 342 325 331
320
297 2iR 27 1
265 90
$0 7s
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ti7
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90 165 190 177
176 262
165 165 135
8 R
8
10 11 15 24
31
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27
21
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37
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11
9 10
IO
10
9 9 10
8
6 .....1 16 -12
o ...... 9 -18
l ...... 11 -13
2 ...... 9 -11