1889.1 14:7 [Haupt. 



opening faTorably to the tidal wave, thus developed and decreased in width 

 from its entrance towards its head, the tide rises higher and higher from 

 the mouth upward. This is due to the concentration of tlie wave by the 

 approach of the shores and to the gradual shoaling of the bottom."* He 

 then proceeds to apply this general statement to the three great bays of the 

 Atlantic coast line, by stating the observed phenomena. I do not wish to 

 be misunderstood as claiming originality for reference to phenomena which 

 are described in elementary teaching. My special claims concerning the 

 dynamic action of the flood tide were limited to the local effects produced 

 at the inlets by the flood as the controlling element, to which I will refer 

 again. The Board do not appear to distinguish sufficiently between my 

 statements of laws and the practical application and observations I have 

 deduced from them. 



The Report continues : 



"Prof. Haupt attributes great importance to the velocities along shore 

 arising from the tidal flow entering these bays. He, however, presents 

 no measurements or other data from which a definite estimate can be 

 drawn as to the intensity of the forces thus generated or comparison made 

 as to their importance when contrasted with the numerous other forces 

 acting upon the bars. Littoral currents, due to the tidal waves, if they 

 exist, are masked and controlled by other forces, and especially by the 

 well-known powerful action of wind-waves on all sandy shores. It rests 

 with Prof. Haupt to demonstrate that his tidal currents flow along the 

 shores of these bays with a velocity sufficient to move the material form- 

 ing the bars, and this he has failed to do. The only argument in favor of 

 this conclusion is an assertion that the general conformation of the bars 

 along the coast accords with what his theory requires. But the facts do 

 not bear this out." 



From the above it would appear (a) that the engineer is expected to 

 make a definite estimate of one of the most variable forces of nature, 

 which may conspire with or oppose others in producing its effects ; (S) 

 that even the existence of littoral currents, due to tidal waves, is doubted 

 by the Board ; (c) if such currents do exist, it must be proven that they 

 have "velocity sufficient to move the material forming the bars;" [d) 

 that no proof has been adduced in support of the proposition enunciated, 

 but merely assertions made to fit a theory. 



In presenting the evidence in reply to this Report, I propose to show : 



(1) That the velocity is an unimportant factor, and that material can 

 be transported even where there is no motion of translation in the motor. 



(3) That waves breaking obliquely on a sandy shore will move the par- 

 ticles over a zigzag path, in a constant direction, which is cumulative. 



(3) That the flood tide produces such angular waves, and that littoral 

 currents aid the movement. 



* Smithsonian Report, 1874, p. 219. 



