4i6 



NA TURE 



[March i, 1894 



gold upon their surface. His theory has been supported by other 

 geologists and chemists. Prof. A. Liversidge has recently 

 made a large number of experiments bearing upon this ques- 

 tion, and his conclusion is that although large nuggets may be 

 artificially produced, those found in alluvial deposits have 

 been derived from gold-bearing rocks and reefs, and have 

 obtained their rounded and mammillated surface by attrition ; 

 also, any small addition of gold which they may have received 

 from meteoric water has been quite immaterial. (Roy. Soc. 

 N.S. Wales, September 6, 1893.) 



Ws have received the annual report of the Geological 

 Survey of Canada for 1890-91 (vol. v. new series). The 

 volume consists of 1566 pages, bound in two parts, and con- 

 taining thirteen separate reports, with maps and illustrations 

 descriptive of the geology, mineralogy, and natural history of 

 the various sections of the Dominion to which they relate. The 

 region surveyed is so large, and the matters described are so 

 numerous, that a bare mention of the results would take up 

 many columns of this paper. One of the points of interest that 

 attracted our attention while glancing through the pages of the 

 report, relates to the discovery of a considerable deposit of in- 

 fusorial earth on the right bank of the Bras, just at its junction 

 with the Montmorency River. The deposit is about fifteen feet 

 thick, and occurs in sand containing boulders, about forty feet 

 above the river, and is overlaid by fifty feet of the same mate- 

 rial. In colour the earth is partly yellowish and partly lead- 

 grey, these tints being sometimes arranged in different layers, 

 and sometimes irregularly intermixed in spots and patches. 

 Another deposit of the same kind has been found on the east 

 side of the north branch of the Ste. Anne River. This deposit 

 is said to extend over an area of half an acre in the river valley, 

 and in places is more than four feet in thickness. Dr. A. R. 

 C. Selwyn, the Director of the Survey, has the thanks of all 

 students of geology for the mass of material he has brought 

 together in the report, and for the manner in which it is 

 arranged and indexed. 



Another Arctic expedition is announced by Reuter's agency 

 as being prepared in the United States by a journalist named 

 Wollman. The proposed route is by Spitzbergen, whence "^a 

 dash is to be made for the pole," and America regained by 

 November of the current year. In this connection it is in- 

 teresting to note that an expedition under the Norwegian 

 Ekroll was stated in the newspapers to have started in June, 

 1893, from the north of Spitzbergen, but from private information 

 we understand that this expedition never set out. The experi- 

 ment of an Arctic journey from this side would be well worth 

 making, if the expedition were properly equipped and adequately 

 organised. 



The recent planimetric measurement of France by the Geo- 

 graphical Department of the Army, gives as the total area 

 536,891 square kilometres, or 206,381 square miles, which 

 is 2000 square miles more than was formerly accepted as 

 the area of the country. The problem of the exact area of a 

 country is one of the most difficult in geography, involving as it 

 does a survey of high accuracy and very laborious computation 

 from large scale maps. The datum is of extreme importance, 

 as it enters into all questions of quantitative distribution ; in the 

 case in point, it reduces the average density of population in 

 France at the census of 1891 from i8y8 to i85'8 per square 

 mile. 



At the last meeting of the Royal Geographical Society, a 

 paper by Mr. Warington Smyth, oh the Upper Mekong, was 

 read in his absence. The journey which was described was 

 carried out for the Siamese Government, with the primary 

 object of investigating a reported deposit of rubies and sapphires 

 NO. 1270, VOL. 49] 



opposite Chiang-kong. Mr. Smyth left Bangkok in December, 

 1892, ascended the Menam for some distance, and crossed the 

 mountainous country inhabited by the kindly and hospitable 

 Laos eastward to the Mekong, which was reached near Chiang- 

 kong. Across the river a series of low hills of crystalline rock 

 gave origin to the gem-bearing gravels carried down by the 

 streams which flowed from them to the main river. These 

 gravels were being actively worked by the Burmese, who tried to 

 keep the place of occurrence of the gems secret. The survey 

 finished, Mr. Smyth's party came down the Mekong, five days' 

 journey amidst beautiful scenery, to Luang Prabang, a large un- 

 walled town of teak houses and numerous picturesque, often 

 ruinous, monasteries. A French store established there seemed 

 to do little business, the people preferring their home-woven 

 cottons to the product of European looms. 



We have received an excerpt paper from the Beobachtnugen 

 der Rleteorologischen Stationen im Kbnigreich Bay em for 1893, 

 containing an account of two balloon ascents, made at night- 

 time, under the auspices of the Munich Balloon Society. The 

 ascents were made for the purpose of investigating the conditions 

 of the atmosphere at a time when the disturbances arising from 

 heated ground were not effective, and the observations have been 

 discussed by Profs. L. Sohncke and Finslerwalder, who also took 

 part in one of the ascents. The instruments recorded automatic- 

 ally, electric light being employed both for attending to them 

 and for obtaining photographic traces from some of the apparatus. 

 The first ascent was made at i a.m. on July 2, 1893, from 

 Munich, there being a barometric maximum at the time, and 

 the second ascent was made on the 8th of the same month, 

 under similar conditions. We can only refer here to one or 

 two of the results of the first ascent. The most important 

 feature in this case was the observation of a maximum temper- 

 ature at a height of about 1000 feet above the ground. At a 

 height of 400 feet the temperature was 63" '5, or 5°"4 higher 

 than at the place of starting. In a stratum of another 450 feet 

 there was only an unimportant rise o^ temperature, after which 

 a rapid fall occurred, so that at a height of a little over 1000 feet 

 the maximum temperature of 65° '8 was recorded, being 7°'7 

 higher than at the place of starting. From this point the 

 temperature steadily decreased, and at 2900 feet it had fallen to 

 56° -3. The relative humidity first decreased regularly with 

 height from 85 to 49 per cent., and then from 1400 feet to the 

 highest point attained (2900 feet), it steadily rose to 72 percent. 



A VALUABLE contribution to the study of thunderstorms, by 

 R. De C. Ward, appears in vol. xxxi. part ii. of the Annals of 

 the Harvard College Observatory, which has just been published. 

 Full details are given of all the storms observed in New Eng- 

 land during the years i886 and 1887. June, July, and August 

 were the months in which thunder was most frequently heard, 

 and July had the greatest number of distinct thunderstorms. 

 The hours of greatest frequency were 5 to 7 p.m. On about 

 40 per cent, of the days when thunder was reported there were 

 storms with progressive movement, the average rate in both years 

 being about 35 miles per hour, while the maximum and mini- 

 mum velocities were 50 and 14 miles per hour respectively. The 

 results of 1886 tend to show that the dependence of thun- 

 derstorms on the larger atmospheric disturbances or cyclonic 

 storms is not so striking as many observations have shown it to 

 be for Europe. While in 1886 over 60 per cent, of the thunder- 

 storms occurred in the southern or south-western quadrant of 

 cyclones central north of New England, in 1887 the majority of 

 the storms occurred in the south-eastern quadrant under anti- 

 cyclonic conditions. A meteorological summary for New 

 England in 1891, by J. Warren Smith, of the U.S. Weather 

 Bureau, appears in the same volume. 



The last number of the Memoirs and Proceeding of the 

 Manchester Literary and Philosophical Society (vol. viii. No. i) 



