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The experiments described by Dr. M. Koernicke in the part in question that while many details not considered October (1904) number of the monthly journal Himmel essential to ordinary readers will be omitted, the principles und Erde prove that both Röntgen and radium rays can of the theories adopted in recent investigations by men of produce a very marked action on plants. The general science, e.g. Prof. Bigelow, in the United States, Dr. Shaw, result of exposure of seedlings was to cause retardation in this country, and Dr. Hildebrandsson, in Sweden, will be and eventually cessation of growth of stem and root; in included. The work will consist of about six parts; the first
cases growth was resumed after an interval, in deals with air-temperature generally, and with the amount others the plants never recovered. The first effect of the of heat received by and radiated from the solid and fluid surrays on dry bean and turnip seeds was to accelerate face of the earth. From a communication from Dr. Hann germination, but while the beans ceased to develop after which we lately published we learn that his elaborate a time, the turnips did not even show signs of retardation ; meteorological charts will, so far as possible, be extended and had the exposure been longer, then undoubtedly the turnips include the important additions to our knowledge made by would also have reacted.
recent expeditions to the Antarctic regions. The latest number of the Isvestia of the Russian Geo
From Dr. Carmelo Scrivanich we have received a short graphical Society (1904, and ii.) contains a further report
pamphlet, printed by the Tipographia sociale of Spalato by Colonel Novitsky on his explorations of the range of
(Italy), dealing with the question of the origin of matter, Peter I., and an interesting and detailed geographical
a subject on which the author invites discussion, sketch by A. Dunin-Gorkavitch of the northern portions of At the present time investigations of the law of force the government of Tobolsk and its inhabitants. The latter between two elements carrying currents (Ampère's and paper is accompanied by a new map of the province, on a allied laws) are commonly regarded as chiefly of academic scale of 27 miles to the inch, which gives with special detail interest. Several papers on this subject have been written the inhabitable portions of this immense region. M. at various times by Dr. Franz Kerntler, of Budapest, and Dubyago gives the results of new pendulum observations in a further paper dealing with the correct law” as claimed by the Urals.
the same author has just been issued by him. It is pub
lished by the Budapester Lloyd Press, and bears the date 1905. A CONFERENCE NUMBER of the IT'est Indian Bulletin has just been published (46 pp.). It relates the agri
The internationalisation of scientific literature is well cultural conference held at Trinidad on January 4-13, and
illustrated by the publication in the Proceedings of the contains the list of the representatives from the several West Indian colonies who attended; an account of the Academy of Amsterdam of a paper in English by Prof.
Sommerfeld, of Aachen, on a simplified deduction of the reception by Sir Henry Jackson, the Governor of Trinidad ;
field and the forces of an electron moving in any given a verbatim report of the presidential address by Sir Daniel Morris; and an abstract of the proceedings at the con
The paper is supplementary to one published in the
Göttinger Nachrichten, and leads to the conclusion that ference and social gatherings. A full account of the
the motion of an electron with velocity exceeding that of papers and discussions will form No. 4 of vol. v. and No. 1 of vol. vi. of the Bulletin, and afford' valuable information light is impossible, as it would require an infinite expendi
ture of force and energy to maintain it, if the electron be on the great progress made in scientific agriculture in the
regarded as a sphere with a uniform surface-charge. On colonies since the Imperial Department was called into existence by Mr. Chamberlain a few years ago.
the contrary, in the case of a sphere with a bodily-charge
the force remains finite. In this problem the electron moves We have received a copy of the meteorological observa- faster than the field of force which it propagates outwards, tions made at the Adelaide Observatory and other places and a “ shadow of motion is produced. A simple illusin South Australia during the years 1900-1901, under the tration might be afforded by comparison with the effects direction of Sir Charles Todd, Government astronomer. produced on a sheet of still water by a disturbance moving Although the rainfall of some districts is still unrepresented, with a velocity greater than that with which the ripples the monthly and yearly results are published for 463 which it produces radiate outwards. stations in 1900, and for 474 in 1901, and these are compared with the averages for previous years. This re
In the “Publicationen des astrophysikalischen Observapresents a very large amount of valuable work, in addition torium zu Potsdam,” No. 41, Dr. Lohse gives the results to that entailed by the usual tables of meteorological results
of a detailed study of the photographic spark spectra of for a large number of stations distributed over the colony.
the metals titanium, vanadium, chromium, manganese, A table is given showing the approximate mean monthly
iron, nickel, cobalt, molybdenum, palladium, tungsten, rainfall over the whole of the agricultural districts from
iridium, bismuth, lead, uranium, zirconium, lanthanum, the year 1861, and the average yield of wheat per acre.
cerium, thorium, and didymium. In the majority of cases It is pointed out that wheat-growing can only be success
the region investigated is from 1 340 to 1 400, but for a fully prosecuted where the percentage of winter rains is
few metals the record is extended towards the red. Thus, largely in excess of that for the summer months, which
the record for iron goes to ^ 446, uranium to 1 431, ziris only usually the case in the southern districts.
conium to 1 471, lanthanum to 1 567, cerium to 1 467,
and didymium to 1 569. The wave-lengths are given to We are glad to be able to announce the issue of part i. the nearest hundredth of a tenth-metre, and a comparison of the new edition of Dr. Hann's excellent “ Lehrbuch der of these with Rowland's wave-lengths for corresponding Meteorologie.” Although so short a period has elapsed solar lines indicates that they are probably correct to since the publication of the first edition, the science has within 0.03 tenth-metre in the mean. Lohse has adopted made such important advances, owing to the results ob- the awkward intensity scale of 0.1 to 10, thus allowing for tained from international balloon and kite observations, and a hundred gradations. Such a large range is neither from the study of the movements of the upper air by necessary nor practicable, and it would have served a means of cloud observations, that some of the older theories better purpose to have kept to the scale i to 10 which have to be modified, and a new edition has been rendered he used in a previous publication on the same subject. necessary. We learn from the notice accompanying the A thorough and detailed knowledge of the spark spectra