AMERICAN ASSOCIATION FOR THE ADVANCEMENT OF SCIENCE. 73 



6. The S. E. and S. W. -winds are in general pretty equally distributed over the 

 moi'ning and evening hours. 



1. The K W. is the prevailing direction of the ordinary sea breeze at Astoria, 

 and San Diego, and the W. at San Francisco. 



Sometimes the W. wind has that character at the first named stations and 

 sometimes the S. W. at the last named. 



A close inspection of the same diagrams will lead to other interesting results. 



Considering the quantities of wind at the three places for the whole year, (dia- 

 gram 'No. 13,) San Diego and Astoria present remarkable similarities, there is 

 more N, E., E and S wind at Astoria, and more N. "W. wind at San Diego. At 

 San Francisco the W. and S. "W. winds give the character to the rose. 



All show the same deficiency of easterly winds, and San Francisco is deficient 

 also in southwardly ones. 



The monthly curves grouped in two periods, from N'ovember to March, both in- 

 cluded, and from April to October, show that the anuual curve has the summer type 

 impressed upon it. 



The K "W". wind prevails in August at Astoria and San Diego, and the "W. and 

 S. W. at San Franciseo. 



There is scarcely any wind from points between North round by east and south. 

 Tlie form of the rose is exceedingly simple, and the generalization very obvious. 



The K E., E., S. and S. "W. winds are considerable at Astoria, and the K W. 

 winds, give the prominent feature to the rose curve. 



As the winter is not the windy season, so the months of March and September 

 are not the windy months. The quantities in the several months and in the several 

 directions are shown on Plate B. On the contrary, July is one of the windiest 

 mouths of the year. 



The further particulars deduced for each of the places of observation cannot be 

 clearly followed without the diagrams. 



ON THE HEIGHTS OF TIDES OF THE ATLANTIC COAST OF THE UNITED STATES, FEOM 

 OBSERVATIONS IN THE COAST STJEVEr. BY A. D. BAOHE, SUPERINTENDENT. 



{Abstract for the Canadian Journal, communicated by the Author.) 



The generalizations resulting from a study of the Coast Survey observations of 

 the tides from Cape Florida to Portland are given in this paper, and are extended 

 by the observations of Admiral Bayfield and Captain Shortland to the coasts of 

 Nova Scotia and New Brunswick. 



The coast is developed into a straight line, and the tidal stations plotted upon 

 it with their actual distances from each other. At each station an ordinate is 

 erected proportional to the height of the tide. The extremities of these ordinates 

 are joined by a broken line, and a curve representing the general average of tbe 

 change of heights is drawn across this line. A model in which vertical wires pro- 

 portional to the rise and fall of the tides are inserted upon a map of the coast, at 

 points corresponding to the tidal stations, shows clearly the law of change of 

 heights. 



In obtaining the curve of heights only the points corresponding to the tidal 

 stations of the outer coast were joined ; so, in the model, wires of diS'erent material 

 represent the outer and inside tidal stations. 



