Haupt] 



152 



[Jan. 18, 



northern flank of the Southern bay, M'here they are best defined and most 

 characteristic. 



From a more detailed analysis of these tables of monthly wind more- 

 ments, quoted from the Signal Service Reports by Lieutenant Carter, 

 U.S.E., for the vicinity of Tybee Roads, Ga , it will be observed that the 

 prevailing winds, which are from theS. and S.W., would tend to move the 

 sand in a direction contrary to its observed motion, which is towards the 

 S.W. To illustrate the relative intensities of the opposing winds, I have 

 collated and compared the total monthly wind movements from 1872 to 

 1886, inclusive. The normal on shore winds is S.E., hence those pro- 

 ducing a north-eastwardly movement are the S. and S.W. winds, and those 

 producing a south-westwardly movement are the E. and N.E. winds. 

 The remaining directions being off-shore. Assembling these in groups by 

 years, they exhibit the following results : 



Ratio 

 in Tliousands 

 of Miles. Excess. 



1872, the S. and S.W. winds : to the E. and N.E. winds, : 



1873 



1874 



1875 



1876, 



1877; 



1878, 



1879: 



1880: 

 1881 

 1882; 



1884 

 1885, 

 1886, 



227-6 



From this comparison it would seem that the forces due to the prevail- 

 ing direction of the wind, and tending to move material to the northeast, 

 are overwhelmingly in excess of those operating in the contrary direction, 

 or as 227,000 is to 6000 miles, an excess of 221,000 miles of wind move- 

 ment from the S. and S.W. over that from the E. and N.E., or 14,733 

 miles per year. 



It would seem, therefore, that the more deeply the wind-wave theory is 

 examined, the more untenable it becomes, and that it is unnecessary to go 

 further, if these tables represent the facts in the case, as I believe they do. 

 Yet before closing this part of the argument, I beg leave to add that on 

 the great lakes the littoral currents are found to divide at or near the widest 

 part of the lakes, and to flow along shore in opposite directions towards 

 the head and outlet, which could not occur were they caused by winds. 

 How could a N.E. wind on Lake Michigan, for example, cause a current 

 to the northward and southward from Milwaukee at the same time ? These 



