May 4, 1882] 



NA TURE 



19 



GEOGRAPHICAL NOTES 

 Lieut. Danenhauer and two of the crew of the ill-fated 

 Jeannette have arrived at St. Petersburg, where they were met 

 with a hearty reception. Lieut. Danenhauer has little hope that 

 Capt. De Long and those with him can have survived, though 

 Engineer Melville is searching for tbem. He speaks of the un- 

 satisfactory nature of the charts of the Lena mouths and that 

 part of the Siberian coast, and states that Baron Nordenskjold 

 has added little to our knowledge in this respect. But the Baron 

 did not profess to do so, and indeed could not, seeing that his 

 aim w as to get over the ground as quickly a-, i ossible. The 

 Lieutenant also is not sanguine as to the possibility of opening 

 up trade by the mouth of the Siberian rivers, forgetting 

 apparently that the time of his arrival at the Lena mouth was 

 past the time most favourable for navigation, and the conditions 

 of his arrival were certainly unfortunate. 



Writing on Chinese maps, the North China Herald says 

 that the present dynasty has made greater efforts at map-making 

 than any former one, and appears to have been the first to intro- 

 duce into them lines of latitude and longitude. The old maps 

 of China are very vague and inaccurate, and are not ancient in 

 any sense. Ssu-ma-Cbien when compiling hi- history did not 

 judge it needful to illustrate it with maps, but his commentators 

 have supplied this deficiency, and recent editions of his work 

 e main maps poorly done of China at successive periods. The 

 geographical works of the Han dynasty do not contain maps. 

 Tre first maps that have been retained in modern editions of 

 ancient books are those of the Sung dynasty, and they seem to 

 be connected with the invention of printing, which dates from 

 a.d. 932. It was the influence of foreign countries that caused 

 the Chinese to enter rigorously into the work of map-making at 

 this period. The Buddhists began to compile works with maps 

 of India and the countries through which lay the routes to India, 

 One of their larger works at this time contains a map of China, 

 of Persia and Rome, according to the geography of the Han 

 dynasty, and a map of India as known to the Buddhists. The 

 Mahommedans followed the lat'er in . teaching their notio is of 

 map-making to the Chinese. But all through the Sung dynasty 

 till the 13th century, when the Mongols established their Empire, 

 Chinese scholars possessed but imperfect views of geography, 

 and failed to obtain clear ideas either of foreign countries or of 

 their own in regard to topography. During the Mongol domina- 

 tion many Europeans visited China and brought w ith them a 

 certain portion of geographical knowledge. No steps, however, 

 were taken by the Government to improve maps and common 

 geographical books, which remained as bad as before. The 

 Chine-e had junks in the Indian Ocean from the 5th century, 

 ye', in the 16th century we find in maps of that time that Cam- 

 bodia and Siam are islands; that Java lies west of Siam, that 

 the Greek empire (Fulin), Arabia, and Medina are three small 

 i-lands a little to the west of Java, and that an immense southern 

 itinent fringes the map from a little south of Ceylon to a point 

 far south of Java, and again farther east. Good maps have 

 only existed since the Jesuit missionaries came to China, and 

 they belong only to the present dynasty. The Emperors Khang- 

 hi and Kien-lung encouraged the survey of their dominions and 

 the construction of good maps. Danville's Atlas Chinois is the 

 result in French of the surveys made under Khang-hi by Ger- 

 billon and his companions. All European maps of China rest 

 mainly on those surveys. Among the atlases of the empire, that 

 made by a former governor of Honan province deserves special 

 praise. It is on a large scale. Each square of 200 li represents 

 a square degree. Two inches and a half represent 200 li. This 

 affords ample space for names, which are freely inserted on the 

 most frequented roads. As a specimen of engraving it is rough, 

 and of course being on wood and done by provincial workmen 

 it cannot equal the copperplate maps which were issued last 

 century from the Government workshops in Peking, but it is 

 in comparison with past times a great advantage to the people 

 to have a map on a lar^e scale for four or five dollars, oa which 

 loth degrees and miles are marked by a system of chessboard 

 -quares with quite sufficient accuracy for ordinary use. For this 

 they are indebted to Khang-hi and the Jesuits. 



Mr. C. R. Markham hns presented to the Geographical 

 Society a long and careful report on the instruction at present 

 supplied to this country in practical astronomy, navigation, 

 route-surveying, and mapping. Although much improvement 

 has taken place since nautical astronomy was placed in the 

 South Kensington programme, still Mr. Markham shows that 



much remains to be done ere practical instruction in these im- 

 portant subjects is on the footing on which it ought to be in a 

 country w hose interests are so dependent on good seamanship. 

 The Council, on the basis of Mr. Markham's report, have made 

 a series of recommendations to the Board of Trade and the 

 Lord -President of the Council ; the former are recommended to 

 raise their standard, and the latter to place navigation and 

 nautical astronomy among the science subjects in the New- 

 Code. The report and the recommendations deserve serious 

 consideration. 



The last two parts of the Deutsche geographische Blatter con- 

 tains detailed accounts, by the Brothers Krause, of their re- 

 searches in the Chukchi Peninsula, accompanied by maps and 

 illustrations ; this forms a valuable addition to the information 

 obtained by the Vega Expedition. Nos. 2 and 3 of the Mitthti- 

 lungen of the Vienna Geographical Society contains a paper by 

 Herr Ferd. Blumentrit, on the Ancestor-Worship and Religious 

 beliefs of the Malays of the Philippine Islands. 



M. Mascart is delivering daily lectures to the naval officers 

 who are to leave on June 1, on the Antarctic Expedition now 

 fitting out at the expense of the French Government. These 

 lectures are delivered at the Pare St. Maur, where instruments 

 have been established. The lecture will be published by 

 Gauthier Villars, after hiving been revised. 



In the April number of Pelermann's Mitthcilungen M. Erne-t 

 Marno gives an interesting account of the barriers of the Bahr-el- 

 Gazal, and their removal from April to June, 1SS1. Dr. Fera 

 Loiol of Prag contribute- a long paper of great interest, with 

 numerous illustration-, on the formation of terrace- in the Alpine 

 valleys. Dr. Oscar Drude writes on the botanical exploration 

 of North Africa from Morocco to Barca. 



"A Visit to Madeira in the Winter 1SS0 Si " is the title of 

 two lectures by Dr. Denis Embleton, of New ca-tle-or.-Tyne, 

 published by Me srs. Churchill. Dr. Embleton, besides giving 

 his own expetience, has brought together much information on 

 the islands in all their aspects. 



The Dutch Polar Expedition, which participates in the 

 great International undertaking, will start for Port Dickson on 

 luly 1 next. Half the cost is borne by the Dutch Government, 

 the other half having been raised by public subscr ption. The 

 expedition will return in 1SS4 if all is well. At the same time 

 the annual Dutch Polar Expedition to the Novaya Zemlya 

 region — the fifth — will start early in May from Amsterdam, 

 commanded by Lieut. Hoffmann. They hope to return in October. 



SOME OF THE DANGEROUS PROPERTIES OF 

 DUSTS 1 



THE lecturer pointed out that the dangerous properties of dust 

 ■*• with which he proposed to deal were altogether distinct 

 from the subtle, invidious dangers of microscopic dust-motes 

 which pervade the air — dangers the existence and nature of which 

 had been fully revealed by the classical researches of Pasteur, 

 Tyndall, &c. 



Compared to those, the dangers which he would discuss were 

 as palpable as are the comparatively gross dust-particles which 

 give rise to them, and yet, although their existence and, to a 

 great extent at any rate, their causes have been known and 

 demonstrated for many years, those who are most directly 

 intere-ted in them and should be most keenly alive to them 

 appear either to have ignored their serious import or to have 

 undervalued the teachings of practical experience and scientific 

 research regarding their causes and effect:. 



Seven years ago Mr. Abel, in a lecture on Accidental Explo- 

 sions, delivered at the Royal Institution, directed attention to 

 the fact that solid combustible and especially inflammable sub- 

 stances, if sufficiently light and finely divided to allow of their 

 remaining for a time thickly su-pended in air, may on application 

 of sufficient flame to them while so suspended, produce explo.ive 

 effects ; behaving, in fact, similarly to mixtures of inflammable 

 gases or vapours with air, with this difference, that the mobility 

 of the molecules of these insures the ready production of com- 

 plete mixtures of them with the air, so that co.i bustion, when 

 once established, proceeds almost instantaneously throughout 

 such mixtures, whereas, in the case of a mixture of solid dust 

 particles and air, the rapidity with which combustion spreads 

 1 Abstract of Lecture at the Royal Institution, April 23, 1882, by Prof 

 F. A. Abel, C.B., F R.S. 



