July 21, 1922] 



SCIENCE 



69 



SCIENTIFIC EVENTS 



MAGNESITE IN SOUTHERN NEVADA 



A MASSIVE deposit of magnesite of unusiial 

 character tbat has recently been brought to 

 the attention of the United States Geological 

 Survey promises to yield a large and readily 

 available supply of this material. The de- 

 posit lies in Clark County, Nevada, in the 

 valley of Muddy River, one of the tributaries 

 of Virgin River, a few miles above the town of 

 St. Thomas. The material has been known for 

 some time as kaolin, and successful experi- 

 ments for utilizing it as a porcelain clay are 

 reported to have been made, though they have 

 not yet resulted in the exploitation of the 

 deposit. The recognized outcrops have been 

 located as mining claims, and some prelim- 

 inary exploration and development work has 

 been done. A side track on the St. Thomas 

 branch of the Los Angeles and Salt Lake Rail- 

 road, about three miles northeast of the north- 

 ernmost group of claims, offers a readily avail- 

 able railroad connection, and the station has 

 been named Kaolin from this deposit. 



The so-called kaolin is stated by the Geolog- 

 ical Survey to be in fact a magnesite and was 

 deposited in a highly magnesia.n sedimentary 

 bed, a part of a regularly stratified series of 

 sedimentary beds exposed by stream channels 

 that cut across a low ridge at the upper edge 

 of Muddy Valley. The deposit foi-ms a 

 chalky-looking bluff, dazzlingly white in the 

 bright sunlight. The material is porcelain- 

 white, fine grained and massive, is remarkably 

 free from foreign material, and has the struc- 

 tureless appearance and conchoidal fracture 

 that are generally characteristic of magnesite. 

 It is not so hard as the more typical mag- 

 nesite, and it crumbles more rapidly on ex- 

 posure to the weather. 



The deposit is included ibetween tilted beds 

 of conglomerate and sandstone below and shale 

 above. The lower contact is sharply defined, 

 but the magnesite grades up into the overlying 

 beds. The purer part of the deposit consists 

 of beds aggregating at least 200 feet in thick- 

 ness. Within the section of purer material 

 there are a few bands of sandy matter, but 

 these are minor in amount and apparently 

 almost negligible, as they could undoubtedly 



be avoided in mining. The whole section lies 

 in the form of a "hogiback" — that is, the softer 

 beds lap up against a unifonn slope of the 

 sandstone and conglomerate that has a north- 

 easterly dip of 30° to 50°. 



The region in which the deposit lies is in 

 large part covered with alluvial wash, which 

 conceals most of the bedrock fonnations, so 

 that the section including the magnesite is ex- 

 posed at only a few places where streams have 

 cut down through the overlying deposits. The 

 regularity of the exposed section and the con- 

 tinuity of the harder beds, which project 

 through the surface wash, justify the assump- 

 tion that the magnesite is practically con- 

 tinuous between exposures and for considerable 

 distances beyond. Its length at the surface 

 seems to be a mile at least. 



THE BRITISH CHEMICAL INDUSTRY 



Sir Joseph Larmor, professor of mathe- 

 matical physics at Cambridge and member of 

 parliament, writes to the London Times as 

 follows : 



I have no claim to expert technical knowledge 

 on chemical matters, but with others I have been 

 wondering what is involved in the announcement 

 in the House of Commons that tlie British Dyes 

 Association are entering into negotiation with 

 the German Color Industry Combine. 



I well remember the remonstrances of scientific 

 chemists when this national venture was placed 

 under the direction of business men and members 

 of the House of Commons early in the war ; hut 

 it was reasonable at that time that the energies 

 of the government that was conducting the war 

 should not be distracted on smaller matters. 



The welcome letter of Sir William Pope sug- 

 gests further questions, to which answers must 

 now be available and possibly instructive. Has 

 the American dye industry, also started during 

 the war, been as hopelessly unfortunate as our 

 own? Have the attempts to develop the fixation 

 of atmospheric nitrogen in this country, on meth- 

 ods which supphed the paramount needs of Ger- 

 many during the war, met with better success? 

 If the industry of fine chemicals is to he worked 

 by British companies supported by the govern- 

 ment, under German direction and instruction, 

 what is to become of the armies of young men 

 who, at the universities, have been undergoing 

 long and expensive training in chemistry, in order 



