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On the Absorption of Certain Crystals in the phenomenon to which Dr. Pupin has given
Infra-red as Dependent Upon the Direction of the name electrical consonance. A primary the Plane of Polarization. By ERNEST MER- circuit alone, and with no condenser, would
have no natural period of oscillation; but By means of a spectro-bolometer the it may have such a period when a neighborwriter has determined the transmission ing secondary circuit contains a condenser. curves for Quartz, Iceland Spar, and Tur
The elastic influence of the condenser is malin out to a wave length of 5.5 fl. In
transferred from one circuit to the other, order to detect the differences between the
on account of their mutual relationship; absorption of the ordinary and extraordinary and the natural period of the primary cirrays the radiation used (that of a Zirconium cuit depends not only upon the value of its lamp) was polarized by reflection before own constants, but those of the secondary passing through the crystal specimen. On
as well. There is a surging of energy back account of diffuse rays from the surface of and forth between the primary circuit and the fiuorite prism considerable difficulty the secondary condenser by intervention was met with in obtaining a pure spectrum;
of their common magnetic field ; the a difficulty which was finally met by using period of these surgings determines the two spectrometers in series ;' i. e., the period of the system. In addition to the spectrum formed by one spectrometer was
graphical analysis, Drs. Bedell and Crethrown upon the slit of another. The re
hore subject the problem to a brief analytsults show that the transmission curves of ical treatment leading to identical results. the ordinary and extraordinary rays are
It is shown that there are two values of entirely independent in all three cases. In
the capacity of the secondary condenser the case of Iceland Spar the differences be
which will give rise to consonance. It is tween the two curves is especially marked, pointed out that a condenser in the secondsharp absorption bands being present in the
ary of the transformer may compensate one curve which are entirely absent in the
for the drop due to magnetic leakage; other. At i= 3.3 y Iceland Spar is found
in fact, this drop may be over-compento behave as turmalin, i. e., the ordinary ray
sated for, so that the secondary potenis suppressed, while the extraordinary ray
tial will actually rise as the transformer is transmitted in considerable amount. The
is loaded down. difference between the two curves is less
Aside from the particular conclusions marked in the case of Quartz, but is very
reached, the paper is of interest for the considerable with Turmalin. In the latter
methods employed, the problem in hand case the two curves are found to intersect,
illustrating well the writer's method of reand in the region lying between the points ciprocal points in constructing admittance of intersection the dechroism of turmalin is
and current diagrams from diagrams of reversed.
impedance and electromotive forces.
Resonance in Transformer Circuits. By F. On the Secular Motion of a Free Magnetic BEDELL and A. C. CREHORE.
Needle, I. By L. A. BAUER. In this article the writers discuss the This article forms the introduction to an action of a condenser in either circuit of a important paper on the secular variation transformer, and develop by purely graphical of terrestrial magnetism which will be conmethods the conditions necessary for primary cluded in the next number. The present resonance due to a secondary condenser, a article is devoted to a description of the the paper.
methods of accumulating and discussing the nature of the simplest sense, pain and gratiavailable data. An abstract is postponed fication, the foundation will have been laid until the appearance of the remainder of for the more complex æsthetic phenomena.
This foundation is believed to consist in the
recognition of a special kind of neurosis for New method of Testing the Magnetic Properties the feelings due to two classes of stimuli of of Iron. By W. S. FRANKLIN.
a very similar but not identical kind. Given In determining the curve of magnetiza- an excessive stimulus which for whatever tion, the sample, in the form of a long nar
reason freely irradiates, and pleasure is felt; row n, is suspended from the arm of a bal- given another stimulus, or the same excesance, the legs of the n being surrounded by sive stimulus with other neural conditions fixed magnetizing coils. The induction
which prevent irradiation and produce a may then be calculated from the weight summation and overflow, and pain is felt. necessary to hold the specimen in equi- Emotion consists (1) of general sensations librium. A novel method of determining of total, organic or irradiating varieties hysteresis loss is also described. In this
which have in common a lack of localization case the sample was in the form of a long and, as a result of associational laws, are rod, and was magnetized by a rather short amalgamated more or less closely with the coil. The rod was suspended from one empirical ego; (2) of more or less explicate part of a balance, and was weighed first
or implicate cognitions (perceptions, intuwhile the coil was moved slowly upward and itions) of the relation between the cause of afterwards during a slow downward motion the sensation and our well-being; (3) the of the coil. A method is developed by emotion is more or less closely attached to which the hysteresis loss may be computed various impulsive expressions which tend in from the difference of these weights. Ex- various ways to intensify the two preceding. perimental data accompany the paper. The psychical element of emotion is essen
New Books. The following books are re- tially intellectual, and the attempt to secure viewed: RAYLEIGH. Theory of Sound, Vol. a serial relation of the faculties' must be 1. POINÇARÉ. Les Oscillations Electriques. abandoned. CARHART. University Physics.
The second paper by M. A. Raffalovich
deals with 'Uranism, or Congenital Sexual THE JOURNAL OF COMPARATIVE NEUROLOGY.
Inversion.' It is a plea for the early recogThe Journal of Comparative Neurology nition of congenital inversion in children for March contains three original papers. and the proper education of such children. The first, Modern Algedonic Theories,' by Inversion is no excuse for debauchery and C. L. Herrick, is a critique based primarily Krafft-Ebbing's pity for the race of inverted upon Marshall's Pain, Pleasure and Æs- persons is largely misplaced. The psychothetics, though most of the other recent logical history of a superior uranist is traced literature is reviewed in the same connec- and commented upon at length. tion. The physiological theory of emotion In a brief paper entitled "The Histogenfinally adopted by the writer is in the main esis of the Cerebellum,' C. L. Herrick a composite drawn chiefly from the nutrition notices the recent work of Dr. Shaper upon theory of Meynert, the discharge theory of the cerebellum of teleosts and calls attenLange and James, and the theory of habit tion to the gratifying harmony between of Gilman. In brief, it is a resistance these results and his own studies published theory. When we have agreed upon the in 1891.
EDITORIAL COMMITTEE : S. NEWCOMB, Mathematics ; R. S. WOODWARD, Mechanics ; E. C. PICKERING, As-
DANIEL G. BRINTON, J. W. POWELL, Anthropology.
FRIDAY, JUNE 21, 1895.
The minimum change in declination along a
parallel of latitude at any particular time, and CONTENTS :
the minimum average secular change along a On the Distribution and the Secular Variation of parallel of latitude during a given interval of time
Terrestrial Magnetism : L. A. BAUER.. ..673 On a Deronian Limestone-Breccia in Southwestern
occur near the equator; both quantities generally Missouri : OSCAR HERSHEY
.676 increase on leaving the equator. Current Notes on Physiography ( X.): W. M. Exactly the reverse is the case with reDAVIS.
..678 Notes on Agriculture (III.): BYRON D. HALSTED..680 gard to the inclination, viz. :Correspondence :
The maximum change in inclination along a The Illustrations in the Standard Natural History: parallel of latitude at any particular time, and ELLIOTT COUES ; C. HART MERRIAM.
the maximum average secular change along a Scientific Literature:
.684 Vermeule's Report on Water Supply; Geological parallel of latitude during a given interval of Survey of New Jersey: ROLLIN D. SALISBURY.
time occur near the equator; both quantities Roscoe's John Dalton and the Rise of Modern Chemistry: EDWARD H. KEISER. Bach's Elas- generally diminish on leaving the equator. ticität und Festigkeit: MANSFIELD MERRIMAN.
These laws were established with the aid The Pocket Gophers of the United States : J. A.
ALLEN. Collett's Norway Lemming : C. H. M. of data scaled from magnetic charts from Notes and News :
1780 to 1885 at points 20° distant in longiAstronomy; General.
tude and in latitudes 60°N, 40°N, 20°N, Societies and Academies :
.698 Biological Society of Washington ; The New Jer- equator, 20°S, 40°S and 60°S. They sey State Microscopical Society.
again point to the same conclusion reached Scientific Journals :
.700 The American Journal of Science.
previously by the writer in a somewhat
different way, namely, that the distribution MSS. intended for publication and books, etc., intended and the secular variation of terrestrial magnefor review should be sent to the responsible editor, Prof. J. McKeen Cattell, Garrison on Hudson, N. Y.
tism appear to be closely related; they are subSubscriptions and advertisements should be sent to SCIENCE, 41 N. Queen St., Lancaster, Pa., or 41 East 49th St., New York. ject to similar laws. It is hence probable that
they are both to be referred primarily to the same ON THE DISTRIBUTION AND THE SECULAR
cause. This common cause seems to be connected VARIATION OF TERRESTRIAL MAGNETISM.
in some way with the earth's rotation. In two papers* read before the Philo- If we regard the earth as uniformly magsophical Society of Washington, May 25th, netized, having its magnetic poles coincithe following main results were obtained :
dent with the geographical poles, and take * On the Secular Variation of Terrestrial Mag
the X axis of a system of coördinates whose netism' and ' A Preliminary Analysis of the Problem
origin is in the center of the earth, parallel of Terrestrial Magnetism and its Variations.'
to the magnetic axis, we shall get the fol
lowing expression for the potential function Now the writer finds that these formulæ at any external point, viz.:
give the mean values of the magnetic ele` = $ ψ = 4 πμ a3.
ments along parallels of latitude with a high
degree of precision. As this paper will be a is the mean radius of the earth, r the dis- printed in full in the American Journal of tance of the point from the origin, and l Science beginning with the August number, the intensity of magnetization per unit of I will select but one typical example. volume.
Latitude I obs'd * I Comp'd 0.-C.
59 .7 N =a = f H. sin o = c. sin o
59 .2 N
+0.5 20° 34 .3N 36 .1 N 1.8
Equator 3.2 S 0.0 w is the geographical latitude and c= tf.
20° 36 .8 S 36 .1 S -0.7 This formula is doubly interesting just
57 .2 S 59.25 + 2.0
60° S 70 .2 S 73.9 S + 3.7 now, as it has been recently deduced empirically by Professor W. von Bezold.* This
Since, according to equation (2). eminent investigator, when considering the
M м mean values of the geomagnetic potential
c = 4 πμ = =H. sec o
a3 along parallels of latitude, found them subject to the simple law 'a= c. sin o = 0.330
we can get a fair value of the magnetic sin 4. Since c = ja y, and the magnetic laborious Gaussian computation by simply
moment of the earth without the aid of the moment, M, of the earth is equal to 1 T 4. a>, we find that von Bezold's empiri- scaling the value of H for equidistant 1 31. a, we find that von Bezold's empiri- points along a parallel of latitude from isocal coefficient implies a value of the mag- dynamic charts and substituting the mean of netic moment equal to 8.52 x 1025 against the values thus found in (6). 8.55 x 1025 as determined by Gauss. We
Thus I get for 1885 as the mean result of thus see the theoretical significance of von
the scalings along 40° N, 20° N, Equator, Bezold's factor.
20° S and 40° S, the value of 0.325 a 3 for Since for the case supposed the horizon
M, against 0.322 a 3 resulting from the 1885 tal component of the intensity, H, is di
Neumayer-Petersen re-computation of the rected meridionally, it follows from (1) that:
But why should the values obtained on the a do
assumption that the earth is uniformly magnetFurthermore, with the aid of simple ized, and its magnetic axis coincident with the transformations :
geographical axis, 80 nearly agree with those V=2 c. sin o
(3) based upon observed quantities ? It seems to F= c. <3 sin? o + 1
me that this opens the question whether tan I = 2 tan o
the asymmetrical distribution of land and V being the vertical force, F, the total and I, the inclination. Formulæ (2), (3), (4)
water is the primary cause of the asymmetand (5) are familiar to every nautical geo- generally supposed. Why do the “anoma
rical distribution of telluric magnetism, as magnetician.
lies' in the distribution so nearly cancel * See his admirable paper ·Über Isanomalen des
each other in going along a parallel of latierdmagnetischen Potentials,' Sitz. berichte d. Kgl. Preuss. Akad. d. Wiss. zu Berlin. Phys.-math. * These quantities are the results of the scalings of Classe, April 4, 1895.
Neumayer's charts for the points mentioned.
tude ? Does this again imply that the ro- the maximum declination. In a word, the tation of the magnetic earth is an important magnetic field which we actually observe can be factor ?
nearly obtained by super-imposing a secondary If we connect by lines all the places on equatorial field upon a primary polar one. the earth's surface having the same de- By comparing the maximum horizontal parture (with due regard to sign) from the intensities of the the two systems, as found values as computed from above formula in the respective magnetic equators, I find we get a series of curves that converge that the polar field is about five to six times around two foci of maximum and minimum stronger than the secondary, and that the axis of departures. I have carried out this idea the resultant system would make an angle of with the aid of my collected data in the about 10° with the rotation axis. case of the inclination for three epochs, 1780, Furthermore, the secular variation phe1880 and 1885. I call the curves thus ob- nomena can be qualitatively explained by tained lines of equal departing inclination, the shifting of just two such poles as beor, briefly, “isapoclinics.' It is especially long to the secondary system. It cannot remarkable that these lines close around be explained by the disturbance of poles on two points not on opposite sides of the opposite sides of the equator. equator, but on the same side.* Their pre- We should thus have to refer both the distribution liminary positions are:
and the secular variation to apparently the same Longitude.
kind of a polarization. For 1885.
This harmonizes with the empirical conNorth end attracting focus, 20°S. 40°W of Gr.
clusions at the beginning of this paper. South end attracting focus, 5°S. 40°E of Gr. For 1780.
Since the intersection of the agonic lines N. F.
50°W. with the equator fall so nearly together S. F.
60°E. with the positions of the isa poclinic foci, a These positions are subject to a slight re
fair idea, perhaps, can be obtained of the vision. The main part, however, is brought shifting of these foci from the motion of the out very clearly in both cases, viz. : that the agonic lines along the equator. I find that chief cause of distortion of the primary sym
both agonic lines have been moving westmetrical field can be represented as due to a
wardly along the equator for the last 300 secondary polarization approximately equatorial years at the average rate of about 0.02 per anin direction.
If the motion continues around the I then showed that the isapoclinics obey equator at this rate the resulting period in a remarkable degree the laws governing
would be about 2000 years, but I do not a magnetic system. They do not run at
wish to be understood as asserting that this random. Thus, for example, the foci or
is the secular variation period. poles of this secondary system fall nearly
A possible third field, which has been on the agonic lines of the actually observed
made probable by Dr. A. Schmidt's beaufield, and the secondary magnetic equator tiful researches, was also pointed out. running roughly north and south marks
Schmidt found, namely, that not the enout approximately the places where occurs
tire observed magnetic effect on the earth
can be referred to a potential; currents * Similar results have been obtained by von Bezold
that pierce the earth's surface seem to make in the paper cited, and by A. von Tillo as seen in his
themselves felt. Perhaps his currents can preliminary paper in Comptes Rendus, Oct. 8, '94, pp. 597-599. It is very much to be hoped that von
be explained thus : If an arbitrarily magTillo's charts will soon be published.
netized sphere rotates in a conducting fluid,