446 



SCIENCE. 



[Vol.. II., No. ."4. 



The Mississippi River levels have been well within this 

 limit. — {Journ. assoc. eng.soc, March.) c. B. G. 



[269 

 GEOLOGY. 

 Lithologyi 



Gold in limestone. — According to Prof. C. A. 

 Sehaeiler, gold occurs in a ferruginous cretaceous lime- 

 stone from Williamson county, Tex. This rock lies 

 near the surface, and fifty-two samples procured in 

 situ by him averaged ,$15.20. Twenty contained no 

 gold, while thirty-two assayed from $1.00 up to $231.50 

 per ton. He regards the gold as having originally 

 existed in the limestone in pyrite, which has since 

 been removed and the gold locally concentrated. — 

 {Trans. Amer. inst. min. eng., Boston meeting.) 

 M. E. w. [270 



The Ottendorf basalt. — Rudolf Scharizer dis- 

 cusses the occurrence, microscopic and chemical com- 

 position, of this Silesian (Austria) basalt, its alteration, 

 and contact phenomena with the grauwake-sand- 

 stone. The paper is quite full of chemical analyses. 

 Olivine, somewhat serpentinized, is the predominat- 

 ing mineral, enclosed in a ground-mass of augite, 

 magnetite, biotite, anorthite, nepheline, etc. The 

 chemical analysis indicates that the rock is closely 

 allied to the peridotites, if it does not belong to them. 

 — (Jahrb. geol'reich., xxxii. 471.) 



The same journal contains an extended paper by 

 Messrs. Teller^and John, on the geological and litho- 

 logical characters of the dioritic rooks of Klausen in 

 the South Tyrol, a series of very diverse rocks in- 

 cluding gabbros or norites. — {Ibid., 589.) m. e. w. 



[271 



METEOROLOGY. 

 The rain-storm in Ontario on July 10. — The 



Canadian meteorological service has made a special 

 investigation of this storm, which caused such un- 

 usual destruction in the vicinity of London, Ontario. 

 Observations from over one hundred observers were 

 received and studied. The isobaric curves show only 

 such imdulations as generally accompany showers 

 and thunder-storms in the summer season ; and there 

 was nothing in the maps to warrant the expectation 

 of any storm, beyond the ' local showers ' which were 

 officially predicted, and which occurred in other parts 

 of Ontario. The fluctuations in barometric pressure 

 were hardly appreciable, and there was but little 

 wind. Indeed, the Only peculiarity of the storm was 

 the unaccountable and unexpected precipitation, 

 which exceeded four inches where the maximum 

 occurred. This araoimt was recorded in an elliptical 

 area of country, extending in a direction about north- 

 west and south-east, and covering a territory of about 

 twenty by fifty miles. The devastation at London 

 was due to the fact that the two branches of the 

 Thames Elver, which there unite, approach from 

 nearly contrary directions, the river flowing away 

 nearly at right angles to the branches. The question 

 is therefore raised, whether it would not be advisable 

 to divert one of the branches, that it may meet the 

 other at an acute angle, and thus lessen the prob- 

 ability of a repetition of the catastrophe. The need 



of an increased number of rainfall observers is 

 pointed out, that means may be afforded for exten- 

 sive study into the little-known subject of the course 

 and causes of local rains. — {Can. wealh. rev., July.) 

 w. u. [272 



GEOGRAPHY. 

 {Atphia.) 

 Ascent of Indrapura, Sumatra. — An account is 

 recently published of the persevering and first suc- 

 cessful attempt of Veth and Van Hasselt, several 

 years ago (1877), to ascend this highest of the Suma- 

 tran volcanoes. They had to choose a way through 

 the dense forest of the lower slopes, and over the 

 sharp, loose rocks nearer the summit; and suddeu 

 heavy rains caused them much delay, so that eight 

 days were silent in reaching the highest point, 

 although the rim of the crater was gained a day ear- 

 lier. Elephant-tracks were not found above 1,500 

 met., rhinoceros-tracks not above 2,600 ; but wild 

 goats had been on the very summit. Above 2,500 

 met., large trees were absent; and above 3,000 only a 

 few plants had found place to grow on the naked vol- 

 canic rocks. The barometer read 482.4 mm., and 

 the thermometer, 8° C, corresponding to a height of 

 about 3,700 metres. The surrounding country had 

 the apjiearance of a uniform forest wilderness, occa- 

 sionally broken by volcanic peaks and ranges, and 

 showing a cultivated region by its lighter color in the 

 distance near the coast. A deep crater lay within the 

 sharp, ragged walls ; several streams ran down to a 

 pool at the bottom, a thousand metres below the rim, 

 whence sulphurous va^Dors and clouds of steam rose 

 into the great caldron. The volcano was in eruption 

 in 1842, when described by Junghuhn. The descent 

 was accomplished without serious difliculties. — 

 {Deutsche geogr. blatter, vi. 1883, 130.) w. m. d. 



[273 

 (South. America.) 



Bolivian rivers. — On the occasion of Dr. E. E. 

 Heath's account of his exploration of the Beni and 

 other rivers flowing from the Andes north-eastward 

 to the Amazon system, Mr. C. E. Markham, secretary 

 of the Eoyal geographical society, gave a general 

 description of the region, part of which he had 

 visited in 1853. The mountains in which the rivers 

 rise are part of the eastern range of the Andes, 

 rising into great peaks like lUimani and lUampu, to 

 a height exceeding 21,000 feet, with fossiliferous Silu- 

 rian rocks up to their summits. To the west is 

 the great interior plateau of the Titicaca basin ; to the 

 east, the rivers descend, bearing gold gravels to the 

 great jjlains, covered with unbroken forest. This 

 eastern region has been very little explored; and the 

 india-rubber and cinchona bark gathered about the 

 upper streams are carried westward over the moun- 

 tains to the Pacific ports, rather than down the rivers 

 to the Amazon and the Atlantic. Markham sketches 

 the history of exploration here from the time of the 

 Inca expedition in the fifteenth century to the expe- 

 ditions of Maldonado down the Amaruraayu in 1806, 

 and Heath down the Beni in 1S80; these being the 

 only travellers who have followed the rivers down to 

 their junction. Dr. Heath mapped the whole course 



