476 SCIENTIFIC RECORD FOR 1885. 



trees were all killed and their fallen and partly decayed trunks are still 

 iyiug on the ground. All appearances confirm the date assigned by 

 Trask, although at that time it was not probably seen by any persons 

 but the Indians. {Science, vi: 46.) 



George Davidson adds to this accounts of smoke seen from a distance 

 to issue from Mount Baker in L854, 1858, and 1870, and seeming to in 

 dicate eruptions of that mountain, but the locality has not been visited 

 and no details of them are known. It is not imjiossiblo that still other 

 evidences of recent volcanic activity may bo found in those sections of 

 our country as they come to be more fully explored. {Science, vi: 262.) 



In the narrative (vol. i) of the Challenger Expedition the volcano of 

 Camiguin Island, which burst forth in 1871, is described and a plate 

 given, which is reproduced in Nature, xxxTi : 250. 



An English Parliamentary blue book (Corea, No. 3, 1885) contains 

 a description by Mr. Carles, the vice-consul at Seoul, of a vast lava field 

 in Corea, which is said to exceed even those in Iceland. {Nature, xxxii : 

 403.) 



In a memoir of 137 pages printed in the Fourth Annual Report of the 

 United States Geological Survey, Captain Button gives a detailed ac- 

 count of his visit to and examination of the volcanoes of the Sandwich 

 Islands in 1882, and applies the results to a discussion of the volcanic 

 problem. He exami ues the various theories suggested by different writers 

 to account for the production of volcanoes, and considers what new light 

 is thrown upon each by his observations, but does not pronounce de- 

 cidedly in favor of any one of the theories stated. 



At a meeting of the British Royal Society (April 16, 1885), Prof. 

 Joseph Prestwich presented an interesting paper "On the agency of 

 water in Volcanic Eruptions" and other related topics. Admitting as 

 an established fact that the vapor of water plays an important part in 

 many volcanic eruptions, it still remains an open question whether its 

 agency is to be regarded as primary or secondary, and how it may have 

 reached that part of the earth's crust where its force must be exerted to 

 produce an eruption. The author reviews the opinions of Daubeny Mal- 

 let and Poulett Scrope, especially of the latter as the explanation most 

 generally accepted by geologists. This holds that the outflow of lava 

 is caused by the expansion of volumes of steam generated in the molten 

 mass beneath the eruptive orifice. The author questions the possibility 

 of water penetrating tlie solid crust of the earth to a sufficient depth to 

 reach a molten magma within, finding a main difficulty in thermo-dy- 

 namic considerations connected with the excessive pressure which must 

 result at comparatively moderate depths and temperatures. But the 

 most weighty objection to the theory is found in the absence of any dis- 

 tinct relation between the discharge of lava and that of vapor. There 

 are numerous instances in the history of Etna, of Santorin, and especi- 

 ally of Mauua Loa where vast discharges of lava have occurred, not 

 only without steam explosions, but with almost the quiet of a water spring. 



