IN RAIN AND SNOW, IN THE UNITED STATES. 



203 



of Type I corresponds to the principal maximum of Type VIII is very weU shown 

 by the curves for Fort McHenry, Washington, and Fortress Monroe on plate 3. 

 The dividing line between Types I and VIII is intermediate between the two 

 last-named stations and well defined. 



Type IX.— Western Coast of the United States, from the Bay of San Francisco to PugeVs Sound. 



Characteristics: A most decided minimum during the summer months, amounting at some places almost to an 

 absence of rain, and a well-marlied maximum late in December. Range, excessive. 





o" 





V E 









u 





S c 









.2 











Mean 



Month. 



c 52 



S s 



c S2 ^ 



d 



of 4 





h >, 



1 1 



^S ^ 



>, 



Stations. 







00 



^- vO t 



'O 











Oh C 









« 



en 



fe fi 







January 



2.6o 



2-IS 



1. 91 I 



88 



2.14 



February- 



1. 71 



1.63 



I. IS I 



37 



1.46 



March 



1.78 



1.97 



1.21 I 



34 



1.58 



April 



•99 



1.02 



.76 



91 



.92 



May 



•37 



•54 



.76 



48 



•54 



June 



•°3 



.04 



•S7 



48 



.28 



July 



.01 



.02 



•43 



13 



•15 



August 



.01 



.01 



.16 



33 



•13 



September 



.06 



•OS 



•51 



65 



•32 



October 



.28 



.29 



•74 



89 



•55 



November 



1.44 



1-31 



I-S9 I 



68 



1-5° 



December 



2.72 



2.99 



2.22 I 



88 



2^45 



The four curves on plate 5 are sufficiently characteristic to require no further 

 illustration. This type appears to have no relation whatever to any of the pre- 

 ceding ones, excepting perhaps the existence of a maximum in December. 



Type X. — Alaska, as observed at Sitka. 



Cbaracteristios : A minimum in June and a maximum in October. Range, excessive. 



This curve is shown on plate 5 ; Types IX and X can not be connected for want of intermediate stations, but it seems 



probable that the maximum of IX in December is shifted to October in X. Tlie minima of IX and X fall in 



the same season of the year. 



The geographical distribution of the rain stations, from which the type-curves 

 were derived, is very unequal. These stations are most numerous in the State of 

 New York and in adjacent States; their location is shown by dots on the accom- 

 panying sketch, diagram 3 ; the strip of shaded area along the sea-coast exhibits 

 the extent of the annual distribution having three maxima and one principal 

 minimum, as given by Type-curve I. These annual fluctuations are so blended 

 that an exact limit for any one type can not, in general, be assigned, though the 

 above boundary for Type I appears quite distmct. 



