552 



SCIENCE, 



[N. S. Vol. IX. No. 224. 



tilted toward the coast. Its surface is studded 

 by innumerable barren peaks and short saw- 

 tooth ranges interspersed by glaciers and nevee. 

 Its edges, on both the costal and inland sides, 

 where the mountains break off abruptly, are 

 etched by short, deep canyons and gulches, 

 which carry off the drainage. The canyon of 

 the Copper alone cuts through the range. 



The northwest rim of the basin in the open 

 fork of the ranges is poorly defined. It lies in a 

 vast plateau-like tundra at an elevation of nearly 

 3,000 feet. The interior of the basin is occu- 

 pied by a plateau-like terrain consisting princi- 

 pally of unconsolidated silts, sands and some 

 gravel. It is horizontally stratified and seems 

 to represent an extensive inland lake-bed or 

 arm of the sea deposit covering several thousand 

 square miles. Through this terrain the Copper 

 River and its tributaries now flow, as a super- 

 imposed drainage, in newly-cut canyon-like 

 valleys, at a depth of Ave or more hundred 

 feet. As bed rock has scarcely anywhere been 

 reached by erosion, the deposit is probably a 

 thousand or more feet in thickness. 



The surface of the terrain slopes gently south- 

 ward and from the east and west toward the 

 center of the basin, where its elevation is about 

 1,500 feet. Back from the streams it is dotted by 

 lakelets and some swamp areas, and is nearly 

 everywhere covered by a fair growth of timber 

 and moss, with local areas of luxuriant grass. 



At the head of Woods Canyon, where the 

 Copper enters the mountains, all trace of the 

 lake beds ceases, denoting apparently the bar- 

 rier which confined the lake before the canyon 

 was cut. The natural features were well illus- 

 trated by original views. 



The rocks in the Coast Range are mostly 

 sandstone, arkoses, slate, mica-schist and 

 quartzites. On its north base some green am- 

 phibolite schist occurs. This schist seems also 

 to form the southwest base of the Wrangell 

 group, but the group itself seems to be mostly 

 volcanic rocks, of which the northwestern end 

 appears to be principally red rhyolite. 



Wm. F. Moesell. 



the philosophical society of washington. 



The 498th meeting of the Society was held 



at 8 p. m. on March 18th, at the Cosmos Club. 



The first paper was by Dr. Artemas Martin on 

 ' Triangles whose angles are 60° or 120° and 

 sides whole numbers.' 



Prom the equation x'' — 2xy cos if> -\- y'^ = z'^ in 

 which a;, y,z denote the sides of any plane triangle 

 and (p the angle included by .r and y, the author 

 deduces the general values 



X = p^ — q", y = 2pq — 2q^ cos <p, 

 z =p'- — 2pq COS 'p -r q^. 



When ^!. = 60°, the sides are 



X =p2 — g2, y=2pq — q^, z =p'- —pq -|- q^ ; 

 and when ^ — 120°, they are 



X =p'—q-, y — 2pq + q% z =2'^ + PQ + t- 



He determines the limitations of the values 

 of ^ and 5 for both cases. The smallest triangle 

 for = 60° is 8, 3, 7 ; the smallest for <p = 120° 

 is 3, 5, 7. 



Numerous examples were given and tables 

 of such triangles were submitted. 



Mention was made of ajjaper on ' The Theory 

 of Commeusurables,' bj^ Edward Sang, pub- 

 lished in the Transactions of the Royal Society 

 of Edinburgh. 



The second paper was by Mr. Lyman J. 

 Briggs on ' Electrical Methods of Investigating 

 the Bloisture Temperature and Soluble Salt 

 Content of Soils.' The abstract of this valu- 

 able paper has not yet come to hand. The 

 third paper was by Mr. C. K. Wead, on 'Appli- 

 cations of Electricity to Musical Instruments.' 

 Mr. Wead said in part : 



Electricity is to-day practically applied on a 

 commercial scale to musical instrnments in 

 three ways : (1) As a motive power to blow or- 

 gans and operate self-playing instruments. (2) 

 To operate the pallets of large organs by means 

 of the electro-pneumatic action patented and 

 introduced by Barker in England in 1868, and 

 shown at the Centennial Exhibition in 1876 by 

 Roosevelt, of New York. (3) To control the 

 application of power to the keys of a piano, 

 the electric circuits being governed by the per- 

 forated paper sheet patented to Seytrein France 

 in 1842 and to Bain in England in 1847. 



Patents have been granted for specific mech- 

 anisms for applying electricity to ring bell 

 chimes and play guitars ; to record the music 

 played on a keyboard instrument ; to sustain in- 



