1889.] NEW YORK ACADEMY OF SCIENCES. 31 



Pkof. Trowbridge made some remarks upon the paper, ex- 

 pressing his interest in the views presented, and stating that he 

 could see no objection to their validity on mechanical grounds, 

 and that he regarded the solution as a very rational one for the 

 facts as described. 



Mr. John Patten spoke of his observations upon the occur- 

 rence of faults of both the kinds alluded to in the article, while 

 engaged in mining operations on the Pacific coast. 



Prof, Martin made some additional remarks, alluding 

 therein to a criticism that had been made on his view, to the 

 effect that a balance would soon be arrived at in a rotating 

 globe, and that then all the parts would move together " as 

 naturally as those of a wheel." That the differential velocities 

 in such cases do produce strains, which are at times sufficient to 

 overcome cohesion, is perfectly familiar in the examples afforded 

 by the occasional violent disruption or "bursting'* of mill- 

 stones and fly-wheels. Usually, the force of cohesion is ade- 

 quate to prevent such effects; but it by no means follows that 

 there are no strains because all the parts are compelled thus 

 to move in apparent accordance. In the case of the earth, 

 where the crust is not so rigid, the effects would be slow and 

 gradual, instead of sudden and violent. 



October 21, 1889. 

 Stated Meeting. 

 The President, Dr. Newberry, in the chair. 

 Ninety-five persons ])resent. 



The paper announced for the evening was then read, and 

 largely illustrated with lantern views ; it was entitled 



researches on sonorous sand in the peninsula of SINAI. 

 BY H. CARRINGTON BOLTON. 



(Abstract.) 



This paper was in continuation of others presented to the 

 Academv bv the author and Dr. Alexis A. Julien, on May 

 14th, 1883, "March 10th, 1881, April 28th, 1881, October loth. 



