Pluviometrical Observations, fyc. 



29 



Art. V. — Pluviometrical Observations, made at West Ches- 

 ter* Pennsylvania ; by William Darlington, M. D. 



TO THE EDITOR. 



West Chester, Penn. Jan. 7, 1828. 



Sir, — About five years ago, I sent you a statement of 

 pluviometrical observations made at this place ; which is 

 inserted in the 6th volume of the Journal of Science, page 

 326. My original design was, to note the quantity of rain 

 and snow which should fall, annually, for a series of years 

 sufficiently extended to afford data for a tolerable estimate 

 of the character of our climate, — so far as those phenomena 

 are concerned. I proposed to myself a period of ten years, 

 as probably sufficient for that object : and as the term is now 

 completed, I offer the result for insertion in the Journal — if 

 you should deem it worthy of a place. 



My former communication contained the observations of 

 the first half of the term proposed ; the present one gives 

 those of the last five years — with an additional column, show- 

 ing the average results for the whole period. 



Synopsis 



of Pluviometrical Observations. 







1 









Average 



Average 



Months. 



1823. 1824. 



1825. 



1826. 



1827. 



the last 5 

 years. 



o/lO 

 years. 



January, 



February, 



March, 



4.1 

 1.7 

 6.9 



5.1 



4.95 



3.5 



2.5 

 4.7 

 5.7 



1.4 



2.5 

 5.3 



2.9 

 4.5 

 2.5 



3.2 



3.67 



4.78 



2.8 



3.485 



4.09 



April, 



1.9 



5.3 



1.4 



3.9 



3.8 



3.26 



3.38 



May, 



4.05 



2.5 



2.8 



0.7 



3.5 



2.71 



4.555 



June, 



2.15 



6.00 



5.8 



8.1 



3.95 



5.2 



4.4 



July, 



6.00 



6.9 



2.5 



2.55 



4.5 



4.49 



4.425 



August, 



5.25 



5.4 



6.1 



2.6 



6.3 



5.13 



4.475 



September, 

 October, 



5.00 

 2.5 



6.2 

 2.00 



2.4 

 2.1 



4.2 

 5.2 



0.8 

 6.5 



3.72 

 3.66 



4.11 



3.73 



November, 



2.55 



2.3 



0.9 



2.4 



5.5 



2.73 



3.615 



December, 



9.3 



3.95 



5.4 



1.2 



4.7 



4.91 



3.855 



Inches. 



51.4 



54.1 |42.3 |40.05|49.45 



47.46 



46.92 



It thus appears, that the average quantity of water which 

 fell, annually, for the last ten years, was 46.92 — or nearly 

 forty-seven inches. The greatest quantity, in any one year, 

 was 54.1 inches, (viz. in 1824) — and the least 39.3 inches, 



* Twenty five miles west of Philadelphia. 



