909 



Chase.] -'^^ [Oct. 1, 



Prof. Mayer laid before the Society an abstract of the pho- 

 tographic observations of the total eclipse of the 7th of Au- 

 gust at Burlington, Iowa, with numerous photographic plates 

 and illustrations. 



Prof McClune exhibited a drawing of the appearance of 

 the Sun to the naked eye made by Prof. Gummere and him- 

 self, and described some of the phenomena of the eclipse. 



Prof. Morton exhibited a copy of the f)hotograpli picture 

 got by Mr. Whipple in 40 seconds, for Prof. Pierce's party of 

 observation; the object being to obtain by a longer exposure 

 than usual with sun pictures, an image of the corona. Photo- 

 graphs of the protuberances required but 5 to 16 seconds; 

 those of the sun before total immersion were exposed but the 

 one 500th of a second, a narrow slit in a flyijig trap-cover 

 serving to sweep a beam of light across the plate. 



Mr. Chase gave the results of his farther discussion of Mr. 

 Dines' weather records in England. 



Pending nominations 627-642 were read. 



And the Society was adjourned. 



TIDAL EAIIFALL BY P. E. CHASE. 



Since the publication of my paper on the Tidal Rainfall of Philadel- 

 phia, (Proc. A. P. S. V. X, pp. 523-537), Mi". Dines has continued his 

 discussion of "the moon's influence upon the fall of rain" (Proc. Me- 

 teorolog. Soc. for April 21, 1869), adding forty years' observations at 

 Chiswick to those at Cpbham, which he had previously examined. 



The evidences which I have adduced of "establishments" in the tidal 

 rainfall, and of more strongly marked characteristics in low latitudes, 

 forbid any general inferences from observations at two stations which 

 are so near each other, and in so high a latitude as Cobham and Chis- 

 wick. But my study of laws that have been developed by records at 

 more than a hundred difierent observatories, in Europe, Asia and America, 

 led me to look for additional confirmation of those laws even in the valu- 

 able abstracts which rendered Mr. Dines so skeptical. I accordingly 

 "smoothed" the irregularities, both in the Cobham and in the Chiswick 

 tables, and arranged and treated in a similar manner President Caswell's 

 observations at Providence, R. I., from December 1831, to May 1860, and 

 the Toronto observations from March 1840, to January 1849. The results 

 arc given in the following Tables. 



