Chase.] no A [1868. 



EXPLANATION OF FIGURES. 



The notched horizontal line, in each figui'e, represents the 

 mean dail}^ or hourly value ; each vertical space represents a 

 deviation of .03 of the mean value, in the rain curves, or of .003 

 of an inch in the barometric curves ; each horizontal space rep- 

 resents a day in the abscissas of the monthly curves, or forty- 

 eight minutes in the abscissas of the dail}^ curves. 



Fig. 1. Total lunar-daily rainfall. 



Philadelphia, 1825-44 ; continuous line. 



Surrey, 1825-44 ; dotted line. ^ 



Fig. 2. Total lunar-daily rainfall at Philadelphia. 



1825-44; dotted line. 



1845—64; brolven line. 



1825-68 ; continuous line. 



Fig. 3. Lunar-daily rains at Philadelphia. 



No. of storms exceeding .25 in.; dotted line. 



Average fall ; broken line. 



Amount of rain in moderate storms ; continuous line. 



Fig. 4. Total hourly rainfall. 



Greenwich, solar hourly ; dotted line. 



Philadelphia ; " " continuous line. 



" lunar hourly ; broken line. 



Fig. 5. Barometric fluctuations at Philadelphia. 



Solar-hourly ; continuous line. 



Lunar-daily ;-----.- broken line. 



Fig. 6. Heavy rains at Philadelphia. 

 Lunar-dail}^ amounts, in storms of 1 inch or more ; dotted line. 



Do. do. do. 1.5 in. or more ; broken line. 



Do. do. do. 2 in. or more : light line. 



Do. do. do. 2.5 in. or more ; heavy line. 



Solar-hourl}-, exceeding .25 in. per hour ; dotted broken line. 



