bluuebunny/crossref_metadata_2025_split huggingface dataset:
Regarding the magnetic effects of the total solar eclipse of August 30, 1905
Authors: Nordmann Ch. 
Published: February 2008

I am pleased that Mr. Chree's remarks on the subject of my article in this Journal (March, 1907) afford me the opportunity of returning to this interesting question, and I beg to make the following observations:1. In the table on p. 20 (loc. cil.) I give for various stations the differences at each instant observed between the force which at each station tends to draw the needle to the east and the value of this same force at Philippeville. I give the values of the forces in terms of 0.1 of my unit which is equal to 0.14γ. Mr. Chree assumes that I guarantee the exactness of these values to the nearest 0.1 of this unit; one will find nowhere in my article any such contention. I have measured, as is usual, the ordinates of the various curves of declination to the nearest 0.1 mm., next, as I have indicated (loc. cit. p. 19), and in order to make all of the curves comparable one with the other, I have multiplied respectively the ordinates by the proper factors in such manner, if I may thus express myself, “as to reduce them to the same horizontal component”. Now these factors reduced for the times from the values of H for the different stations and from the angular values of the curves in millimeters are none of them integral numbers, but fractional. I have thus naturally given the values of the table in question to the nearest 0.1 of my unit; as it is always the custom in like cases, I have not felt authorized to drop the last decimal which results from the measures and calculations for the different times for fear of introducing new errors.
Note on the magnetic effect of winds
Authors: Humphreys W. J. 
Published: February 2008

It is known that lightning discharges produce temporary disturbances of the Earth's magnetic field in their neighborhood, often of magnitude sufficient to produce departures of several millimeters on the records, but no disturbances have been detected that could certainly be traced to the movements of charged clouds.However, since a moving charge is an electric current, it follows that charged clouds as they drift by, and ionized winds with an excess of either positive or negative electrons, must produce magnetic fields, at right angles to their line of motion, whose disturbance of the Earth's field depends upon the direction and the speed of the winds, and upon the kind and extent of their electrification.
On the probable existence of a magnetic field in sun‐spots
Authors: Hale George E. 
Published: February 2008

The lines in the spectra of Sun‐spots differ from those of the ordinary solar spectrum mainly through changes of intensity and width. Most of the spot lines are more or less widened, some of them are double, and a few are triple. These characteristics of the lines, and the fact that the revolution of electrically charged particles in a solar vortex might be expected to produce a magnetic field, led to a search for evidences of the Zee man effect in Sun‐spot spectra.Light from a spot was passed through a Fresnel rhomb and Nicol prism, mounted before the slit of a spectrograph of 30 feet focal length, used in conjunction with the tower telescope of the Mount Wilson Solar Observatory. Photographs of the spectra were made in the third order of a Rowland grating, having 14438 lines to the inch. It was found that the relative intensities of the components of the double lines in the spot are reversed by rotating the Nicol through an angle of 90°. The widened lines are also shifted when the Nicol is rotated. Just such changes are observed if the same doublets are examined under the same conditions along the lines of force of a powerful magnetic field.
On the apparent alterations of mass disclosed by weighings of magnets
Authors: Bauer L. A. 
Published: February 2008

I am of course very much interested in Dr. Lloyd's communication in this issue of the Journal. As he states, the question investigated was one which arose incidentally in the course of my investigation as to the limits within which we may assume a strict coupling of the Earth's magnetic forces. The following paragraphs are quoted from p. 33 of my paper, which as stated in the title was a “Preliminary Report:”“In the course of this investigation I was led to make some experiments with regard to the first question which concerned Norman—whether magnetization altered the weight, or say mass, of a magnetizable substance. As I have not had the leisure to bring the experiments to a conclusion on this point, the present results should be regarded merely as preliminary to a more serious undertaking. They are herewith given primarily with a view of inciting experimentation on the part of others. I shall be greatly obliged if any one will bring to my attention any past experiments on this point other than those of Norman, as also any future experiments.”
Magnetic charts of the island of Sardinia
Authors: Palazzo L. 
Published: February 2008

Several years ago I had the honor of presenting to the readers of Terrestrial Magnetism the magnetic chart of Sicily. I now venture to believe that some magnetic charts of the second in importance among the large Italian islands, Sardinia, would not be out of place in this Journal, especially as Sardinia reveals even more pronounced and characteristic magnetic features than Sicily.The values of the magnetic elements which I have utilized for the construction of the charts, are essentially those which I determined since 1892, during a journey through the Island, by commission of the Direction of the Italian Central Meteorological Office. At a former date, viz., in 1884, magnetic measurements had been carried out at a few points of Sardinia, by Prof. Chistoni, my predecessor in the Meteorological Office. But since Chistoni's station‐points were considered insufficient for the tracing of magnetic lines, it was decided to resume observations in 1892. I have re‐occupied nearly all the points selected by him, and besides have added numerous new points to the chart. Within the same locality, I have frequently made measurements at two different points distant from each other a few kilometers or fractions of kilometer, with the object of bringing to a more satisfactory solution some doubts which had arisen concerning the existence of magnetic local disturbances.
Ueber den elektrischen strom Erde‐Luft und seinen zusammenhang mit den Erdströmen und dem schwankungen des erdmagnetischen Feldes
Authors: Gockel Von Dr. A. 
Published: February 2008

Die Frage, ob ein Teil des magnetischen Erdfeldes seine Entstehung den in der Erde oder den zwischen der Erde und der Atmosphäre circulierenden elektrischen Strömen seine Entstehung verdankt, ist in neuerer Zeit vielfach behandelt worden.Man hat nach Zusammenhängen zwischen den Schwankungen des Potentialgefälles1 und denen der magnetischen Grössen gesucht. Zölss2 hat auf einen solchen zwischen dem Gang der Leitfähigkeit und der Deklination aufmerksam gemacht. Es ist aber klar, dass, wenn ein ursächlicher Zusammenhang zwischen den elektrischen und magnetischen Elementen überhaupt existiert, er in erster Linie zwischen den letzteren und dem elektrischen Vertikalstrom und nicht dessen einzelnen Komponenten existieren muss. Leider lagen von der doch weitaus wichtigsten luftelektrischen Grösse, dem elektrischen Vertikalstrom, bis in die neueste Zeit herein nur vereinzelte Bestimmungen vor. Man hat sehr häufig das Potentialgefälle, in neuerer Zeit nicht viel weniger häufig die elektrische Leitfähigkeit oder den lonengehalt der Atmosphäre gemessen, aber nur von sehr wenigen Observatorien sind Beobachtungen veröffentlicht, aus denen sich das Produkt von Potentialgefälle und Leitfähigkeit, der Vertikalstrom, berechnen lässt. Ganz vereinzelt nur wurden direkte Messungen dieses letzteren gemacht.
Magnetic observations on the day of the solar eclipse of April 17, 1912, at De Bilt
Authors: Van Dijk G. 
Published: February 2008

With reference to the article by Mr. O. H. Tittmann1 concerning the solar eclipse of April 28, 1911, it seems to me of interest to give here some communications about the magnetic registrations at De Bilt (Lat. 52° 6′N., Long. 5° 11′=0h 20m 44s E. of Gr.) at the time of the solar eclipse of April 17, 1912.The magnetic condition of the Earth in April, 1912, may be inferred from the following list, containing the mean magnetic character (scale 0, 1, 2 of Innsbruck) from April 6 to 25, computed from the data of 42 magnetic observatories given in “Caractère magnétique de chaque jour des mois Avril‐Juni, 1912”:
L'eclipse du 17 avril 1912 à Lu‐kia‐pang (Chine)
Authors: de Moidrey J. 
Published: February 2008

M. Kalinowski, dans une récente communication1 relative à l'éclipse du 17 avril dernier, manifeste le désir de voir les observations d'une station plus orientale que Varsovie. Lu‐kia‐pang étant dans ce cas, je vous envoie copie des courbes très calmes de ce jour. J'y joins la courbe moyenne des trois éléments à Zi‐ka‐wei, en avril, moyenne de onze ans, à la même échelle.dD. 1 mm.=0′.48 dH. 1 mm.=4γ.66 dZ.1 mm.=7γ.6
Regarding improvement of appliances for measurement of the Earth's magnetic elements by magnetic and electric methods
Authors: Bauer L. A. 
Published: February 2008

On April 1, 1914, the Department of Terrestrial Magnetism of the Carnegie Institution of Washington enters upon the eleventh year of its existence, and in quarters specially designed for its various needs. In its new home (see Plate I), the requisite facilities are provided for coping, in as successful manner as possible, with the many problems of general physical interest, or of an experimental nature, continually arising in the course of such an undertaking as a general magnetic or an electric survey of the Earth. Here the attempt is made to supplement the existing agencies for observational research in cosmical and terrestrial physics by laboratory research.The work at present being conducted in the subjects of terrestrial magnetism and atmospheric electricity, is mainly observational: Either the magnetic or electric elements are determined at suitably distributed points over the Earth with the view of obtaining, as accurately as possible, a knowledge of its general magnetic or electric condition (magnetic or electric surveys), or at a considerably smaller number of points are registered the variations to which the magnetic and electric elements are subject with time and with varying planetary and solar conditions (observatories). There are thus magnetic and electric surveys, and magnetic and electric observatories; but hitherto there has been no laboratory for the specific purpose of broad physical research in problems of common interest to observational and experimental work, in brief, the same kind of happy combination of laboratory and observational facilities as has already proved successful in other sciences, as in astrophysics, for example.
The theory of electrical dispersion into the free atmosphere, with a discussion of the theory of the Gerdien conductivity‐apparatus, and of the theory of the collection of radioactive deposit by a charged conductor
Authors: Swann W. F. G. 
Published: February 2008

Riecke has shown that if a charged sphere is placed in a stream of air, it loses its charge at a rate given by

urn:x-wiley:00968013:media:tma3642:tma3642-math-0001
where Q is the charge on the sphere, n is the number per c. c. of ions of opposite sign to the charge Q, ν is the specific velocity of these ions, and e is the ionic charge.The deduction of the expression (1) is not as simple as might at first sight appear, and it is necessary to be on one's guard against forming a proof which, while leading to the result (1), is unsound in principle; in fact, the expression (1) would not be true for quiescent air. It is only true, as Riecke has pointed out, when there is an air‐current of sufficiently high velocity to enable us to neglect the effects of diffusion, reformation, and recombination of ions. Riecke obtained the expression by calculating the paths of the ions under the combined action of the field and of the air velocity. In a previous communication I have shown that the expression is true for a uniformly charged wire, but, as far as I know, no general proof has been given that the relation holds when the air does not flow in parallel stream lines with uniform velocity, and when the charged body has any arbitrary shape. The truth of the result, under the conditions stated, seems, however, generally to have been assumed in consequence of the experimental fact that a freely exposed body loses its charge at a rate proportional to the charge. It is the object of the first part of this paper to give a proof for the general case.
The atmospheric‐electric observations made on the second cruise of the Carnegie
Authors: Hewlett C. W. 
Published: February 2008

The atmospheric‐electric observations, of which an account is given in this report, were made in pursuance of the plan of work assigned to the Carnegie by Dr. Bauer, the Director of the Department of Terrestrial Magnetism of the Carnegie Institution of Washington. The observers received at all times the cordial support of Captain Peters, who, throughout the cruise, was in command of the vessel. The final reduction and discussion of the observations have been made under the direction of Dr. Swann.Atmospheric‐electric observations on board a sailing ship are attended with peculiar difficulties, some of which up to the present have not been sufficiently overcome to insure the degree of accuracy obtained in similar work on land. Chief among these difficulties is that of finding the proper factor for the reduction of the observed values of the potential‐gradient, so as to obtain the values which exist in the undisturbed open. The changes which take place in the relative positions of the sails and yards with respect to the rest of the ship introduce variations into this redaction‐factor, so that it is necessary to determine the latter for several arrangements of the sails. On account of the flying spray in the air, it is rather difficult to secure proper Insulation in the potential‐gradient observations. The difference of potential between the points occupied by the two collectors is a rapidly fluctuating quantity on account of the rolling and pitching of the ship, so that if the collectors take up the potential of the air around them fairly rapidly, it becomes difficult to make an estimation of the mean value of the electroscope‐reading.
The mean value of a function of spherical polar coordinates round a circle on a sphere
Authors: Bateman H. 
Published: February 2008

Some years ago von Bezold pointed out that the mean value of the magnetic potential round a parallel of geographical latitude is very nearly equal to a constant multiple of the cosine of the north polar distance. Shortly afterward Adolf Schmidt considered the problem of finding the diameter of the Earth for which the mean value of the magnetic potential round each small circle with the diameter as axis, approximates in the best way to a constant multiple of the cosine of the polar distance from one extremity of the diameter. Schmidt chose as the criterion for obtaining the best approximation the condition that the square of the difference between the two quantities just mentioned, when integrated over the whole Earth, should be a minimum.While reading Schmidt's paper, in connection with some studies at the Department of Terrestrial Magnetism during the past summer, it occurred to me that it might be useful to have a simple formula for the mean value of a function round a circle on a sphere. Such a formula can be deduced without much trouble from the formulæ for the transformation of spherical harmonics in a transition from one set of polar coordinates to another. These formulæ have been given by Adolf Schmidt, but the particular theorem we are interested in is not explicitly mentioned in his paper. A more direct proof of the theorem may be obtained by using a certain property of potential functions, and is perhaps worth recording.
Solar radiation and terrestrial magnetism
Authors: Bauer L. A. 
Published: February 2008

1. One of the foremost magneticians of the last century, after a lifelong and devoted study of the various phenomena of the “Earth magnetical,” said in a public address: “Viewed in itself and its various relations, the magnetism of the Earth cannot be counted less than one of the most important branches of the physical history of the planet we inhabit.” I shall endeavor to show briefly, in the paper which I have the honor to present before you, the rôle certain terrestrial‐magnetic phenomena may play in the study of the physical characteristics of our atmosphere, especially of those upper levels, 100 kilometers and more above us, to which man has not yet succeeded in sending his exploratory instruments.2. Among the most striking of the Earth's magnetic phenomena is the diurnal variation which takes place chiefly during the daylight hours, and varies in its magnitude and general characteristics with geographic position with the season of the year, and with Sun‐spot activity. A preliminary mathematical analysis, made by Schuster and presented before the Royal Society of England in 1889, led to the conclusion that “the principal part of the diurnal variation is due to causes outside of the Earth's surface, and probably to electric currents in our atmosphere.” Furthermore, Schuster found “that the horizontal movements in the atmosphere which must accompany a tidal action of the Sun or Moon or any periodic variation of the barometer, such as is actually observed, would produce electric currents in the atmosphere having magnetic effects similar in character to the observed diurnal variation.” In brief, the hypothesis adopted by Schuster to account for the supposed electric currents, generated in the upper atmospheric regions, was the one first proposed by Balfour Stewart—that the necessary electromotive forces for the production and maintenance of the required electric currents are generated by the motion of masses of conducting air across the lines of the Earth's permanent magnetic field, chiefly of the vertical component, thus bringing into play Foucault currents.
Cruise of the Carnegie from South Georgia to Lyttelton, New Zealand, January 14 to April 1, 1916
Authors: Ault J. P. 
Published: February 2008

I beg to transmit the following report of our trip from South Georgia to Lyttelton:The Carnegie left South Georgia at 7 P. M., January 14, 1916, towed out of harbor against a heavy head wind by the steam whaler Fortuna. In the days that followed we realized that we were in climatic conditions quite different from what we had previously experienced. Icebergs appeared in increasing numbers, and fog was almost continuous. We will long remember January 18 as the only day during the entire trip of four months when we failed to obtain observations for the magnetic declination. The sun was visible for only three seconds during the entire day, giving no opportunity for observations.
Preliminary report on the results of the Aurora‐Borealis expedition to Bossekop in the spring of 1913. (fifth communication.)
Authors: Störmer Carl 
Published: February 2008

1. In this Journal for September, 1913, March and December, 1915, and June, 1916, I published preliminary reports on my aurora‐borealis expedition of the spring of 1913. The present communication relates to the material of the last two nights, March 30 and April 1, 1913, comprising about 90 auroral photograms.Fig. 1 shows the distribution of calculated altitudes of auroras above the surface of the Earth. These altitudes are not as concentrated around the 100 km. level as in the corresponding cases of March 14–15 and 16 to 29, mainly owing to the fact that the auroras of April 1–2 were all very faint and relatively tranquil.
Diurnal and annual variation of magnetic bays at Zikawei, 1877–1908
Authors: de Moidrey J. 
Published: February 2008

The Bulletin Magnétique de Zikawei has been publishing, since the service was transferred to Lukiapang, a summary of the perturbations which Dr. C. Chree has designated as bays, that is, those which consist in a single oscillation such that the curve resumes afterward approximately its former position, the bay being entirely on one side of what would have been the normal curve. It has seemed well to investigate such bays in the magnetograms obtained at Zikawei during the period March 1877 to March 1908.I. Diurnal variation. The time is noted when the greatest departure of the bay from the normal position occurs. The number of such occurrences is determined for each hour of the day for the whole period; 0h. 5 denotes the interval from 0h to 1h, civil time of Zikawei, etc. These numbers, reduced at first on the basis of 100 per hour, gave a mean, with reference to which the deviations or differences were taken, the latter being then smoothed by the method of the double mean. This work was done for the 31 years, 6 of which were of magnetic calm (1878, 1879, 1888, 1889, 1900 and 1901), and 6 of magnetic activity (1883, 1884, 1892, 1893, 1905 and 1906). Tables 1 and 2 and Fig. 1 represent these deviations.
Note concerning the measurement of ionic density on the top of a tower
Authors: Swann W. F. G. 
Published: February 2008

On pages 35–37 of the March issue of the Journal for the current year, P. L. Mercanton gives some very interesting results of measurements of the atmospheric ionization made by him on a parapet near the top of a tower, and in the interior of the tower at its base. He finds that if n+ and n− refer, respectively, to the positive and negative ionic‐densities, n+/n− is much larger for the measurement made in the strong electric field near the top of the tower than in the zero electric field in the interior of its base. Thus, for n+/n− as measured at the top of the tower, values 4.33, 2.16, 4.46, and 1.70 were obtained on four different occasions, while the corresponding values for the foot of the tower were, respectively, 1.31, 1.09, 1.24, and 1.19.I wish to call attention to the confirmation, afforded by these observations, of the view put forward in my former communication1 as to the effect of the charge induced on the Ebert ion‐counter by the potential‐gradient in modifying the values obtained in ionic‐density measurements. The theory of the phenomenon shows that, for a potential‐gradient of the normal sign, measurements of n+ should be unaffected by the induced charge, while those of n− should be too small. The effect of the negative induced charge on the instrument is to retard the velocity of the approaching negative ions. Thus, these ions move slower than the incoming stream of air, with a result that a smaller number of them enter the instrument per second than would enter if there were no induced charge. The positive ions are accelerated by the induced charge, but theory shows that the excess number of ions entering the instrument is just equal to the number which are captured by the outer cylinder of the apparatus, so that the measurements of n+ are unaffected by the induced charge.
Values of the magnetic elements at the Samoa Observatory
Authors: Angenheister G. 
Published: February 2008

The values for the years 1909–1916 are preliminary ones; they may require slight corrections of a few tenths of a minute for declination and inclination, and a few gammas for the intensity components. The final values of I and Z for 1909 and 1910 must be deferred.The tabular quantities are based upon “Stationstheodolit Tesdorpf 2025” and “Stationsinductor Schulze 2.” The values have not yet been referred to the International Magnetic Standards (I. M. S.), as determined from the extensive comparisons of the Department of Terrestrial Magnetism; the relations which may serve for the reductions to I. M. S. are given on next page.