216 Scientific Intelligence. 



the coast gradually emerged from the water at the close of that 



Features such as we have described have frequently been 

 noticed in river valleys, but we are not aware of any instance 

 where so large a number of short valleys, none of them more 

 than ten miles long, present in so striking a manner the pecul- 

 iarities mentioned. 



That the cause is a general one seems probable. As sug- 

 gested by Prof. Dana, who recently visited the island, the form 

 and direction of the valleys in question may have arisen from 

 the combination of motions to which Prof. Kerr of North Caro- 

 lina attributes similar phenomena in tin- -mtli eastward (lowing 

 streams of that state. "The cause," Prof. Kerr observes, "is 

 doubtless the rotation of the earth upon its axis co-acting with 

 the river current" To a like combination of motions Prof. 

 Maury, in 1855, referred some of the phenomena of ocean cur- 

 rents. The principle is the same that is exemplified in the 

 Q of ocean waters, in which, as a writer observes, 

 " Any waters flowing from the polar regions (where the earth's 

 motion is slow) toward the equator, would be thrown mainly 

 against the west side of the oceans * * for they have no 

 power to keep up with the earth's motion." 



A similar result occurs with southward flowing streams over 

 the land. For this reason the bank upon the west side of the 

 stream is continually driven against it, in consequence of which 

 the bank is abraded by the current, and worn away. 



SCIENTIFIC INTELLIGENCE. 



I. Chemistry and Physics. 



1. On Rock-rri/ttai /;.//,,,„,>./„ .,„,,,_ 77,, rm ,> ine t J:r ^ lf}/ J qra'ht- 

 1 >.—Stein, who, in 1874, proposed the manufacture of 

 standard linear measures and wei-'hN in r»rk .-r\>t:il, now goes 

 farther and suggests the manufact a 



circles for telescopes, theodolites and qua. Smuts, and even ther- 

 mometers, of this material. With reference to weights, he states 

 that the spherical form has been ad.pt, ,1 j„ ,,,-. tcrence to the 

 for many reasons, among others, because it is cheaper. 

 For balance-beams, and scale-pans, the lightness of quartz, •>■<&. i* 

 in its favor, aluminum being only 2-61 ; moreover its unall 



~ eomplet'e. The construction presents no 



special practical difficulties. Graduated circles are cut from a 



dicular to the axis. For thermometer-, a rod 



used for the linear unit can be bored lengthwise and the 



tube polished, an enlarged reservoir being made at the bottom for 



