1889.] 151 tHaupt. 



port the sand and drift in the direction of these extended spits. If the 

 direction of the beach and drift movements are to be taken as indicative 

 of that of the prevailing winds, as they should be, if the wind theory be 

 true, then we must have the winds in the vicinity of Nantucket blowing 

 from the S.W. ; those at New York entrance from the S.E. ; those along 

 the Jersey coast from the N.E. ; those at Cape Henlopen from the S.E. ; 

 those along the " Eastern Shore " from the N.E. ; those from Chesapeake 

 Bay to Cape Hatteras from the S.E., and from Hatteras to Georgia from 

 the N.E., with sudden reversals at Capes Fear and Lookout, aud so on. 

 In short, to fit this theory, the prevailing winds must blow from diflferent 

 quarters over limited sections, which the observed results, as plotted from 

 the Hydrographic Charts, do not confirm. But, on the contrary, the flood 

 component is found to approach in the direction of the shore drift and satis- 

 tactorily to explain this movement. The wind-wave theory also fails 

 signally as applied to the Great Lakes. 



The same defect of the wind-wave theory exists when applied to the 

 Gulf of Mexico, for in a special Report* on Galveston, by a board of en- 

 gineers, dated New York, January 21, 1886, occurs this statement as to 

 the potency of the winds in producing changes on the bar : 



"Twenty and one-half per cent of the winds were from the N.E. and 

 E. ; their waves should give a south-westerly motion to the sand : thirty- 

 six per cent were from the S. or S.W. ; these should move the sand 

 towards the north-east." 



But, as a matter of fact, the resultant sand movement is south-westerly, 

 or in a direction opposed to the prevailing wind ; so that this theory is un- 

 tenable in almost, if not in every instance. 



The movements of the winds in the great Southern Bay may be seen 

 from the subjoined statement of the Signal Service for this bay for the 

 sixteen years from 1871 to 1886 : 



AVEEAGE FREQUENCY OF WINDS, AS INDICATED BY THE NDMBEE OF OBSERVATIONS. 



From which it appears that there is not a single year in which the pre- 

 vailing winds are from the N.E., but that they are generally from the S. 

 and S.W. Hence if the forms of the spits and channels be due to these 

 forces, they should be just the reverse of those found to exist along the 



* Report Chief of Engineers, Appendix S, 1886. 



