214 



Mr. Hennessey on Rainfall ^c. 



[Dec. 12, 



which is in opposition to the popular behef on the subject. I enclose the 

 Table, on the chance of its proving sufficiently interesting to be noticed. 



Average daily fall of rain between successive quarters and at each quarter 

 of the moon from 1st of May to 31st of October of each year, measured 

 at the Office of the Superintendent of the Great Trigonometrical Survey 

 of India. The office stands in Mussoorie, on the most southern range 

 of the Himalaya Mountains, lat. N. 30° 28', long. E. of Greenwich 

 78° 7' ; height above mean sea-level 6500 feet. 



Year. 



Average Daily Pall. 



iotai J? au 

 from May 

 1 to Oc- 

 tober 31. 



) to« 



9 



• to 3) 



D 



D too 



O 



O to ) 



) 



1854 , , , . 



1855 



1856 



1857 



1858 



1859 



1862 



1863 



1864 



1866 



inch. 

 •644 

 •456 

 •732 

 •280 

 •402 

 •665 

 •356 

 •685 

 •611 

 •348 

 •762 

 •543 

 •135 



inch. 



•374 

 •204 

 •745 

 •319 

 •448 

 •263 

 •228 

 •678 

 •620 

 •342 

 [•409 

 •235 

 •360 



inch. 



•813 

 •360 

 •703 

 •794 

 •485 

 •253 

 •430 

 1-014 

 •513 

 •862 

 •545 

 •276 

 •402 



inch. 



•176 

 •918 

 •237 

 1^013 

 •298 

 •642 

 •719 

 •372 

 •651 

 •932 

 •292 

 •120 

 •580 



inch. 



•630 

 •311 

 •397 

 •521 

 •518 

 •306 

 •564 

 1-332 

 •364 

 •511 

 •394 

 •443 

 •636 



inch. 



•096 

 •356 

 •588 

 •136 

 •157 

 •253 

 •205 

 •287 

 •852 

 •595 

 •328 

 •526 

 •809 



inch. 



•512 

 •753 

 •347 

 •368 

 •705 

 •570 

 •301 

 •577 

 •645 

 •291 

 •237 

 •518 

 •452 



inch. 



•621 

 •733 

 •340 

 •606 

 •373 

 •583 

 •073 

 •855 

 •530 

 •546 

 •352 

 •785 

 •483 



inches. 



100-72 

 85-85 

 93-28 

 88-27 

 84-61 

 78-31 

 65-81 



14M6 

 93-91 

 93-03 

 82-19 

 76-37 

 8M5 



Means of ] 

 columns J 



•509 



,•402 



•573 



•535 



•533 



•399 



•483 



•529 



89^589 



Greneral mean of • 3) O ) 0-466 inch. 



General mean of ) to @ to ]) , ]) to O, q to ) 0-525 „ 



Note. — The rainfall during the preceding twenty-four hours was mea- 

 sured daily at mean noon. Suppose m^, m.^, m^, m^, ni-, m^, m^, m^, to de- 

 note nine such consecutive measurements of daily rainfall, registered at 

 Mussoorie mean noon, respectively on the 1st, 2nd . . . 9th of the month, 

 and that the moon entered her first quarter at an hour nearer to noon of 

 the 1st than to the preceding or succeeding noons. In this case the arith- 

 metical mean of and has been entered in column ]) as the average 

 daily fall at the first quarter. Similarly, if full moon occurred nearest to 



noon of the 8th, the quantity ^ has been reckoned as the average 



n ■,, 1 m^-\-m.-\-m--\-m,.-\-m„ . 

 daily fall at full moon ; and ~ — represents the average 



daily fall from }) to O- The foregoing Table has been prepared under 

 these conditions by Baboo Dwarkanath Dutt, Computer to the Great Tri- 

 gonometrical Survey of India. 



