624 



NA TURK 



[OcTtJliER 29, 1896 



(3) The position of the radiant point. 



(4) The character of the radiation, whether sharply defined 

 or diffuse and scattered over an area. 



(5) If an area, find its diameter, and if possible its shape, 

 whether elliptical or round. 



(6) The apparent Ijrightness of the meteors, how many are 

 equal to, or brighter than, first magnitude stars. 



(7) The duration of the active display. 



(8) The duration of the entire shower. 



(9) Does the radiant point, as derived on several nights of 

 observation, retain a fixed position or move eastwards amongst 

 the stars? In investigating this feature, it will be necessary to 

 observe the place of the radiant on each night of the shower's 

 visibility. Kour or five meteors, if accurately recorded and in 

 or near Leo, will generally be sufficient to indicate a correct 

 position. On nights when the shower is very rich, it will be a 

 good plan to get the radiant from successive half-hourly or 

 hourly intervals, and then, from these indejjendent observations, 

 to derive a mean position for the night. 



( lol The duration of the meteor flights in individual cases. 



(11) The proportionate number of Leonids leaving streaks to 

 the total number counted. 



(12) The time of duration of the streaks. In the case of 

 streaks lasting for some minutes, their drift amongst the stars 

 should be noted. 



(13) The colour of the meteors and of their streaks. 



There are some other points, but these are among the 

 most important. 



As to the numerous minor showers of the jieriod, these 

 must be neglected if the desire is to specially observe 

 the Leonids. Many Taurids are usually seen at the 

 middle of November, but these are easily distinguished 

 from the Leonids, as they move slowly and rarely leave 

 streaks ; moreover, their radiant point is placed in a 

 ■different quarter of the heavens. 



To adequately observe and record a meteor shower, 

 at least two persons are necessary, for it is quite im- 

 possible for a single observer to give proper attention to 

 all the features. He cannot register the apparent paths 

 and count the number of meteors visible, as his attention 

 will be frequently withdrawn from the sky, and many 

 meteors will altogether elude him. To determine the 

 maNJmum time of a shower, the observer's attention must 

 be continuously directed to the heavens, and he must 

 carefully note at intervals, say of five minutes, the 

 number of meteors seen. To chart the observed tracts, 

 to determine the radiant, and to note a few other features, 

 quite monopolises one person's attention, and requires an 

 extensive experience for the work to be done properly. 

 . Whenever a special meteoric display such as the Leonids 

 is intended to be observed, the services of an assistant 

 are necessary to reckon the visible number of meteors, 

 and determine the time of their maximum frequency. 

 Though the ensuing return of Leonids is not likely to be 

 sufficiently important to call for special effort, there is 

 need of our being prepared, as it may exceed expectation 

 and should be suitably recorded, and it will be sure to 

 ■offer many interesting facts for observation and discussion. 

 W. F. Denninc. 



THE INTERNATIONAL METEOROLOGICAL 

 CONFERENCE IN PARIS. 



A S has already been announced, this meeting was 

 •^~*- held in September, under the presidency of Prof. 

 Mascart, and lasted seven days (September 17-23, in- 

 clusive). The last meeting of a similar character had 

 been held in Munich in 1S91. The Paris meeting was 

 attended by some forty members. Canada and Mexico 

 were represented for the first time ; neither .Spain, Por- 

 tugal, Hrazil, nor the Argentine States were represented. 

 The Weather Bureau, Washington, sent no one ; Mr. 

 Page came from the Hydrographic Office, Washington, 

 but only in a private capacity. 



Dr. Hann's absence from the meeting, on the ground 

 of health, was universally regretted. 



NO. 14C9. \-OI.. 54] 



The programme for discussion consisted of over forty 

 questions, and to these Mr. Wragge, of Brisbane, pro- 

 posed to add more than a score ; but several of his 

 applications were ruled as iillra I'ircs for the Conference. 

 Some of the questions on the programme were set aside 

 as either reopening discussions w-hich had been closed 

 years ago, or as being impossible of acceptance ; as, for 

 instance, one as to the adoption of a |)eriod of 26'67928 

 days for all meteorological and magnetical phenomena. 



The business really done was, briefly, as follows ; — 



Committees were appointed, as already announced 

 (N.\TURE, October i), to carry on investigations into 

 (i) terrestrial magnitudes and atmospheric electricity ; 

 (2) cloud observations ; (3) balloon ascents ; i4) sun- 

 shine and radiation. 



It was recommended, at the suggestion of Mr. .Symons, 

 that systematic comparisons of different forms of ther- 

 mometer exposure be carried out generally, .■\ssmann's 

 apparatus for ventilating thermometers to be one of the 

 forms tested. 



The Conference declined to make any recommendation 

 as to a standard anemometer, or as to anemometer 

 exposure. 



Several applications were made to the Conference to 

 exert, by resolutions, pressure on Governments wnth the 

 view of the obtaining of grants for investigations ; but 

 these were all ruled as ultra J'l/rs. Mr. Wragge's 

 requests for stations in Tasmania, and for observations 

 on Mount Wellington, Tasmania, and also on Mount 

 Kosciusko, in .■\ustralia, were met by the general declar- 

 ation that the Conference must welcome the establish- 

 ment of good stations all over the world. 



Dr. Neumayer's proposals to modify existing systems 

 of meteorological telegraphy in Europe were not accepted. 



I'our questions as to the discussion of phenomena in 

 cyclones were held to be purely theoretical, and therefore 

 unsuitable for discussion at a Conference. 



Prof .Mohn submitted some proposals as to the use of 

 the hypsometer. No discussion ensued, but Prof Mohn"s 

 paper will be printed iu the appendix to the Report of the 

 Conference. 



Dr. Paulsen, of Copenhagen, exhibited monthly ice 

 charts of the North .\tlantic, north of the 60th parallel, 

 and received a promise of assistance in their completion 

 from the members present, who were in a position to 

 obtain observations of ice. 



Dr. .Snellen, of Utrecht, requested the Conference to 

 take measures for convening a new .Maritime Conference, 

 to carry on further the work done at the London Con- 

 ference of 1874. This matter was referred to the Inter- 

 natiotial Committee. 



The chief feature of the Paris meeting was the attention 

 paid to terrestrial magnetism and atmospheric electricity. 

 The Committee appointed for these subjects held three 

 meetings, of which the minutes will shorty appear: 

 and, as has already been stated, a Committee has been 

 nominated to carry on the discussion of various points 

 which have been raised. 



Finally, the International Meteorological Committee 

 has been reappointed with a few modifications, owing to 

 resignations, &c. Its members now are — 



Dr. von Bezold (Germany). 



Dr. Billwiller (Switzerland). 



Admiral Capello (Portugal). 



Mr. Davis (.\rgentine Re- 

 public). 



Mr. Eliot (India). 



Hofrath Hann (.\ustria). 



M. Ilepiles (Roumania). 



I'rof. Hildebrandsson (Sweden). 



I'rof Mascart (France), Presi- 

 dail. 



I'rof. Mohn (Norway). 



I'rof. W. L. Moore (United 



States). 

 Dr. Paulsen (Denmark). 

 Mr. Russell (New South 



Wales). 

 Major-Gencral Rykalchefi' 



(Russia). 

 Mr. Scott (England), &-,7v/rtO'. 

 Dr. Snellen (Holland). 

 Prof. Tacchini (Italy). 



Kiij;i:Rr H. ScOTT, Sci. In/. Mel. Couimiltci 



