6o 



NATURE 



\^Nov. i8, il 



Occultations of Stars by the Moon (visible at Greenwich) 



Reap. 



Correspondinc 

 angles from ver- 

 tex to right for 

 inverted image 



U Cephei o 522 ... 81 16 N. ... Nov. 28, 2 27 m 



fGeminorum ... 6 57-4 ... 20 44 N. ... ,, 23, 21 30 v1/ 

 S Canis Minoris ... 7 26-5... 8 34 N. ... ,, 24, M 



S Sagittarii 19 128 .. 19 14 S , 21, M 



n Aquilae 19 467 ... o 43 N. ... „ 24, o o M 



M signifies maximum ; >n minimum. 

 Meteor Showers 

 The Aiiiiromcdes, maximum November 27, R.A. 24°, Decl. 

 44° N., form the most interesting shower of the week. A 

 radiant near /i Persei, R.A. 60°, Decl. 49" N., supplies very 

 swift meteors ; swift meteors are likewise seen from a radiant 

 near 17 Ursas Majoris, R. A. 208°, Decl. 43° N. 



GEOGRAPHICAL NOTES 

 The Bulletin of the Paris Geographical Society for the present 

 year (Nos. i and 2) contain several papers of interest. We need 

 do no more than mention M. Ch. Mannoir's annual report on 

 the progress of geography during the past year, which fills 130 

 pages. M. Grandidier writes on the rivers and lagoons of part 

 of the east coast of Mad.agascar, and M. Gouin, of Nam-dmh, 

 contributes a long paper on Tonquin, which deals with the com- 

 mercial geography of the country rather than with the geography 

 proper. No. 2 opens with the report of a strong Committee of 

 the Society on the orthography of geographical names, which 

 will be read with interest. No elaborate or exhaustive reforms 

 are proposed ; the suggestions are rather a series of simple modifi- 

 cations "based on good sense rather than on high philological 

 science, which is only accessible to the few initiated." The 

 Committee take up the programme of the Roy.al Geographical 

 Society, " completing it in some respects, and making some addi- 

 tions sensible to musical ears." The bases of the proposals are 

 the same as those of our own .Society : (I) not to seek an abso- 

 lute perfection in the representation of sounds ; (2) to preserve 

 in European names the form of the country of their origin ; (3) 

 to retain in the case of other places the mode commonly em- 

 ployed. M. Rolland contributes a long paper on the hydro- 

 graphy and oroiraphy of the Algerian .Sahara ; and M. Marteil 

 examines the map of the French establishments on the Senegal 

 recently issued by the Ministry of Marine. Lieut. Baudens 

 describes a trip which he made last year along the Black River 

 of Tonquin ; and finally there is an .account written by Dr. 

 Potagos in 18S0 of a journey which he made in the Pamir in 

 1870, including a visit to the famous Yakub Beg of Kashgar. 



We have received the Ver/iandlnngen (Bd. xiii. No. S) and 

 the Zcitschrift (Bd. xxi. Nos. 4 and 5) of the Geographical 

 Society of Berlin. The first contains, ouly one paper, but that 

 an interesting one, by Dr. Sievers, on a recent journey in the 

 Sien'a Nevada de Santa Marta, in Columbia. The object of 

 the journey was to study the geology and phy.^ical geography of 

 the region, and especially to ascertain whether these mountains 

 belong to the system of the Andes or not. As Dr. Sievers has 

 only been back for a short time, he w.as unable to give any 

 definite results, and he confines himself to describing the course 

 of the journey, and to mentioning important points necessary 

 for a proper understanding of the physical geography of the 

 region. In the Zeitsehrift, Herr Jung continues and concludes 

 his analysis of the Indian census of 18S1 ; this is followed by a 

 translation, from the Proceedings of the Russian Geographical 

 Society, of Dr. Iwanow's paper on certain ancient monuments 

 discovered by him in the course of a geological examination of 

 Turkestan. Prof. Gelcich has a highly technical history of the 



methods of ascertaining the area of a country, and Dr. von 

 Danckelmann one on the frequency of rain in the Indian Ocean. 

 Herr Sandler makes a contribution to the history of cartography 

 by giving an account of the life and works of Johann Baptista 

 Homann, a geographer of the latter 'part of the seventeenth 

 century. A curious map appended to this paper (which is of 

 considerable length) shows, by means of white and red outlines, 

 the world .according to [jresent cartography and according to 

 Homann's niap^. The number concludes with a short paper on 

 the hot springs of Kamchatka. 



In a recent work on the geol igy and geography of Sumatra, 

 M. Verbeek, a Dutch engineer, says that sixty-seven volcanoes 

 are known to exist on that island. There may be more even 

 than this, for parts of the north-west, which are covered with 

 primaeval forests, have never been penetrated. Two only of 

 these are active, Merapi and Talang (or Soclau), the former 

 being 2892, and the latter 2542 metres in height. 



The October issue of the Bollettino of the Italian Geographical 

 Society contains an account of an excursion made during the 

 summer by E. Modigliani to the rarely visited island of Nias, 

 which lies some thirty miles from the west coast of Sumatra, a 

 little north of the equator. The explorer spent two months in 

 the place, but owing to local feuds was unable to penetrate 

 beyond Fadoro, a large village near Telok Dalam Bay on the 

 south side. The natives, apparently of Malayan or Indonesian 

 stock, but speaking a language quite different from Malay, and 

 by Crawfurd described as ** a simple, mild, and primitive people," 

 he found on the contrary to be fierce and treacherous savages, 

 everywhere addicted to head-hunting. Their hostility was such, 

 that he failed to make any botanical or zoological collections ; 

 but fortunately secured eleven huniiin skulls from the southern 

 districts, which have been sent to the Anthropological Museum 

 of Florence. No similar specimens appear to have hitherto 

 reached Europe, nor are any found even in the Batavian collec- 

 tion. Head-hunting is taken so much as a matter of course, that 

 on Sig. Modigliani offering to purchase some skulls, the rajah of 

 Bavolovalani on the south coast quietly remarked that it would 

 be rather an expensive business, as an expedition would have to 

 be specially fitted out and sent to the hills to raid upon some 

 neighbouring tribes and carry off the required number of heads. 

 He had no idea of craniological specimens being collected except 

 from the living subject. The interior of Nias still presents a 

 promising field of exploration, never having been visited by any 

 European travellers. 



LIGHTHOUSE ILLUMINANTS^ 

 II. 

 "^.— Range of Lights in Hazy Weather 

 ■T^IIE observations on this subject of the Trinity House Com- 

 mittee have served to confirm the conclusions .announced 

 by M. Allard in his " Memoire sur I'intensite et la portee des 

 phares," 1876, and in his more recent "Notes sur quelques 

 objections relatives a I'emploi de la lumiere electrique dans les 

 phares." The Committee find that the gas and oil lights which 

 are equal in clear weather are equal also in fogs ; that in rather 

 dense fog the more powerful light had but little advantage over 

 the less powerful, for example, "the triform electric appearing 

 at 1500 feet, while the quadriform gas and triform oil showed up 

 together a little before the observers reached 1400 feet," and 

 that the electric light, while suffering, according to the photo- 

 metric results, a somewhat greater loss in hazy we.ather than the 

 flame lights, is "visible at a greater distance than the highest 

 powers tried in gas or oil." Using M. AUard's formula, which 

 appears to rest on well-established physical and physiological 

 data, I have calculated the range in fogs of various degrees of 

 thickness of some of the lights exhibited at the South Fore- 

 land. The range of a light, or the limit at which it is just 

 lost or just picked up, is that limit at which its intensity is 

 diminished by distance and haze to the minimum intensity per- 

 ceptible by a good eye, such as the practised eye-i of seamen are. 

 M. Allard gives this minimum intensity, on the authority, of 

 "des experiences qui ont ete faites sur ce sujet an Champ de 

 Mars," as th.at of l/loo Carcel at a distance of one kdometre on 

 a perfectly clear night. This corresponds to J candle at a dis- 

 tance of one nautical mile. When the air is not perfectly clear, 



' Further Report of Mr. Vernon Harcourt to the Board of Trade on 

 the Experimental Lights exhi' ited at the South Foreland. Continued from 

 p. 46. 



