Meteorological Observations. 



XXXI 



Abstract of the Results of the Hourly Meteorological Observations 



taken at the Surveyor General's Office, Calcutta, 



in the month of April 1869. 



Monthly Eesults. 



Mean height of the Barometer for the month... 



Max. height of the Barometer occurred at 9 a. m. on the 1st. 



Min. height of the Barometer occurred at 5 p. at. on the 16th. 



Extreme range of the Barometer during the month 



Mean of the daily Max. Pressures 



Ditto ditto Min. ditto 

 Mean daily range of the Barometer during the month ... 



Inches. 



29.756 

 22.968 

 29.530 



0.438 

 29.834 

 29.680 



0.154 



Mean Dry Bulb Thermometer for the month 

 Max. Temperature occurred at 3 & 4 p. m. on the 6th. 

 Min. Temperature occurred at 3 a. m. on the 16th 

 Extreme range of the Temperature during the month 

 Mean of the daily Max. Temperature ... 



Ditto ditto Min. ditto, 

 Mean daily range of the Temperature during the month. 



86.5 

 99.5 

 75.0 

 24.5 

 95.2 

 79.6 

 15.6 



Mean Wet Bulb Thermometer for the month ... 



Mean Dry Bulb Thermometer above Mean Wet Bulb Thermometer 



Computed Mean Dew-point for the month 



Mean Dry Bulb Thermometer above computed mean Dew-point . . . 



Mean Elastic force of Vapour for the month ... 



78.6 



8.0 



73.7 



12.8 



Inches. 

 0.819 



Troy grain. 



Mean Weight of Vapour for the month ... ... ... 8.73 



Additional Weight of Vapour required for complete saturation ... 4.37 

 Mean degree of humidity for the month, complete saturation being unity 0.67 



Mean Max. Solar radiation Thermometer for the month. 



o 

 131.6 



Inches. 



Rained 7 days, — Max. fall of rain during 24 hours ... ... 0.12 



Total amount of rain during the month ... ... ... 0.20 



Total amount of rain indicated by the Gauge attached to the anemo- 

 meter during the month ... ... ... ... ... 0.11 



Prevailing direction of the Wind S. S. W., & S. W. 



