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NEW YORK STATE MUSEUM 



precipitation by geographic districts, and (7) excessive precipita- 

 tion. 



The chapter on " Excessive precipitation " is probably, from an 

 engineering point of view, the most important. Mr Henry states 

 that in 1888 attention was first directed to the importance of 

 statistics of excessive rainfall. At the present time the Monthly 

 Weather Review pnblishes a table of maximum rainfalls in five 

 and ten minute and one hour periods, etc. 



Table No. VIII of Mr Henry's paper gives details of excessive 

 rainfall at Washington, Savannah, and St Louis, and table 

 Xo. IX gives maximum intensity of rainfall for periods of five, 

 ten, and sixty minutes at the Weather Bureau stations equipped 

 with self-registering gages, compiled from all available records. 

 Inasmuch as this paper may be readily referred to further detail 

 is omitted. 



Measurement of rainfall. The subject, " How close may rain- 

 fall be measured?" has been fully discussed by Prof. Cleveland 

 Abbe. 1 Professor Abbe states that the influence of altitude was 

 first brought to the attention of the learned world by Heberden 

 who, in 1769, in a memoir in the Transactions of the Royal Society 

 of London, stated that a gage on Westminster Abbey, over 150 feet 

 above the ground, caught less than half as much as a gage at the 

 ground. 



Profs. Alexander D. Bache and Joseph Henry, and Mr Desmond 

 FitzGerald have studied the question extensively in this country. 

 Mr FitzGerald's results may be found in the Journal of the Asso- 

 ciation of Engineering Societies for August, 1881. 2 



Mr FitzGerald kept two gages, one at a hight of 2 feet 6 inches 

 above the level of the ground, and the second at a distance of 150 

 feet from the first, and at an elevation of 20 feet 4 inches above 

 the lower gage. Both gages were 14.85 inches in diameter. 



1 Determination of the True Amount of Precipitation and its Bearing on 

 Theories of Forest Influences, by Cleveland Abbe: Appendix I of Bulletin 

 No. 7, Forest Influences ; Forestry Division, United States Department of 

 Agriculture. 



2 Does the Wind Cause the Diminished Amount of Rain Collected in 

 Elevated Rain Gages? By Desmond FitzGerald: Jour. Assoc. Engineering 

 Societies, Vol. Ill, No. 10 (August, 1884). 



