English (United Kingdom)

https://curated-unify.zendy.io/wp-json/zendy-region/v1/featured_content/oa?rat=en

https://curated-unify.zendy.io/wp-json/zendy-region/v1/highlighted_journal/

Global: Zendy Plus annual

Presents the access of premium content as premium feature

Premium Content

Presents the keyphrase highlighting as premium feature

Keyphrase Highlighting

Presents the summarisation as premium feature

Summarisation

Insights

Presents the pdf analysis as premium feature

PDF Analysis

Presents the zaia usage as premium feature

ZAIA

Global: Zendy Tools annual

Global: Zendy Free Plan

Global: Zendy Tools monthly

Global: Zendy Plus monthly

From the conclusions in my former articles, (1),1) (2),2) (3)3) and (4),4) it is now obvious that the type-change of diurnal magnetic varia tions in a subtropical observatory is not a local phenomenon, but a world-wide one, which, further is likely to have some relations with the solar activity. The present paper gives a brief description of how the field of diurnal magnetic variations progressed with time round the earth on those particular days now under consideration. Some of the horizontal vector diagrams of the diurnal magnetic variations on June 21 and 23, 1934 are shown in Fig. 1, and those on Sept. 23 and 24, 1933 in Fig. 2. On examining these diagrams,atten tion is called to the direction of rotation and the direction of X com ponent of the main partof the variations with regard to the day time. In some of these diagrams, the relations of the above two directions are inconsistent with those deduced from the ideal diagram of the Schuster-Chapman theory. These seem to take place mostly in the following cases : when the field distribution is deforming its shape during the east-west progress : when the field of negative and positive potential pass successively through an observatory in a day : when the equipotential line are of wave form. An interesting case of the last is when the principal positive or negative potential area has two centers. In Fig. 1 the change of vector diagrams at Zony, Aso, So Ses and Antipolo is quite continuous, and justify what we have mentioned in the papers (1), (3) and (4). It can be seen that the center of the principal negative potential passed near Zo Ses on the 21st, while on the 23th it passed south of and not far from Zony. Diagrams of Watheroo and Christchurch are somewhat complicated, being affected by the areas of potential of both signs, as can be inferred from the figures in (4). At Alibag, Helwan and Karsani, also at Honolulu and Apia, the course of variations appears to have a tendency opposite to those at stations situated near the meridian 120'E. At North American observatories, the reversal of type of variations is quite obvious while in Europe it is rather obscure. Much need not be added to explain Fig. 2, for the diagrams in dicate a relation similar to those in Fig. 1, except that the rotation on the 23rd at Aso and So Ses is clockwise, being affected by the secondary center as illustrated in the corresponding chart in (4) and in Fig. 3 of this paper. At Kakioka this latter influence is sowewhat smaller.

On the Progressive Change of the Field of Diurnal Variations of Terrestrial Magnetism