824 



SCIENCE 



[N. S. Vol. XXV". No. 647 



is confirmed; but the amount of tte change 

 is less than one half that found by Koppen, 

 the deviation being only 0°.13 C. on each 

 side of the mean. 



The general conclusion was that if the sun's 

 radiation of heat is variable at aU, the amount 

 is too small to have any appreciable meteor- 

 ological effect. 



It was distinctly set forth that the research 

 referred only to the radiation of heat, and not 

 to the electric radiations which are known to 

 proceed from the sun, which vary from time 

 to time and which are related to magnetic 

 storms, and perhaps also to the atmospheric 

 electricity. 



In the course of the general discussion of 

 Professor Newcomb's paper, Dr. Abbott ex- 

 hibited some diagrams showing the variations 

 of terrestrial temperatures corresponding to 

 certain variations of solar radiation as derived 

 from bolometric measurements at a mean lati- 

 tude of 39°.6 N. He called attention to other 

 curves he had constructed showing the annual 

 temperature variations observed at coast and 

 inland stations in the United States, the varia- 

 tion at the inland stations being three times 

 that at the coast station. Another curve was 

 shown of an hypothetical earth (earth assumed 

 as a black body) which truly followed the 

 variation of solar radiation. 



At the conclusion of the meeting Dr. Abbott 

 called attention to a disc photometer which he 

 had recently designed, and which he afforded 

 the society the opportunity of seeing in opera- 

 tion. E. L. Faeis, 



THE GEOLOGICAL SOCIETY OF WASHltfCTON 



At the 189th meeting of the society held in 

 the Cosmos Club on Wednesday evening, 

 March 20, the president announced the receipt 

 of a letter from the Washington Academy of 

 Sciences stating the intention of the academy 

 to erect a building to be devoted to the use of 

 the scientific societies of Washington, and ask- 

 ing that the Geological Society indicate the 

 amount of room needed and how much it 

 would contribute to the building fund. Action 

 concerning the matter was deferred to the next 

 meeting. 



Regular Program 

 The following papers, illustrated by lantern 

 slides, were presented : 



Some Features of the Geology of Magdalena 

 and Black Range Region, New Mexico: C. 

 H. Gordon. 



The area to which this paper relates lies 

 along the west side of the Rio Grande Valley, 

 extending from near the north line of Socorro 

 Coimty southward to Deming. The valley of 

 the Rio Grande here is from twelve to forty 

 miles in width and is bounded on the west by 

 several parallel mountain ranges which consti- 

 tute the southeastern border of the Great 

 Plateau country as outlined by Dutton. In 

 the Black Range a nearly complete sequence 

 of Paleozoic rocks occurs, resting upon the 

 eroded surface of pre-Cambrian granites and 

 schists. In the Magdalenas the Lower Car- 

 boniferous limestone rests directly upon green- 

 stone schists and granites. Rocks of Creta- 

 ceous age occur in a number of places, resting 

 , upon the eroded surface of the Pennsylvanian 

 series. No Tertiary sedimentaries were ob- 

 served, this period being characterized by ex- 

 tensive eruptions of andesite, and rhyolite. 

 Intrusions of monzonite and quartz-monzonite 

 and their associated porphyries are common, 

 and with them occur also granite porphyries, 

 and rocks of basic composition like diabase. 

 Remnants of extensive fiows of basalt occur, 

 resting upon the mesa gTavels filling the valley. 

 Structurally the region is characterized by 

 block faulting. With the uplift of the pla- 

 teau on the west there appears to have been a 

 relative sinking of the belt now represented 

 by the Rio Grande Valley, with crustal break- 

 ing and readjustment giving rise to tilted 

 blocks which appear here and there as eleva- 

 tions rising out of the general plain level. 

 Extensive erosion has supplied from the ad- 

 joining slopes a vast amount of debris which 

 covers the valley in places to a depth of from 

 1,000 to 2,000 feet. 



At the north end of the Magdalena range 

 near the town of Magdalena are located the 

 lead and zinc mines of Kelly. The ores occur 

 along the bedding planes of carboniferous 

 limestones which have a westward inclination 



