6 14 



Proceedings of the Roi/al Irish Academy. 



General Conclusions and Remarks. 



August is the warmest month as regards the mean temperature and the 

 mean maximum and mean minimum. January is the coldest except in respect 

 of the mean minimum temperature, which falls in February. The temperature 

 curves for the years are remarkable for their flatness, indicating a small range 

 of temperature-variation, especially over the months December, January, 

 February, and March, and over the summer months June, July, and August. 



The difference between the mean minimum and mean maximum is small, 

 and is nearly constant from month to month. The highest temperature 

 recorded is 82'0°F. in June, 1887, and the lowest is 20 , 0°F. in January, 

 1894. 



4. Humidity. 



The data presented in Table IX were compiled from the manuscript 

 copies of the monthly summaries of Blacksod. The means of the dry-bulb 

 and wet-bulb thermometers refer to readings taken at 8 a.m. for a period of 

 thirty-five years (1871-1905). The Blacksod records began in 1899 ; but the 

 means were estimated and " weighted " in the usual manner by reference to 

 suitable stations. The values for dew-point and percentage-humidity were 

 calculated by means of Glaisher's factors. The employment in these calcula- 

 tions of the differences between the monthly means of the dry-bulb and wet- 

 bulb temperatures, instead of the monthly means of the differences, is 

 unsatisfactory. It is, however, recognized by the Meteorological Office ; and, 

 following the rule in such cases, the percentages are only given in whole 

 numbers. The annual humidity percentages for Valencia, and Markree 

 Castle (Co. Sligo), are given for comparison. The values in these two cases 

 refer to observations made at 9 a.m., and are based on a twenty-five years' 

 record (1881-1905). 



Table IX. 





Jan. 



Feb. 



Mar. 



Apr. 



May 



June 



July 



Aug. 



Sept. 



Oct. 



Nov. 



Dec. 



< 



Mean Dry-Bulb, 

 Mean Wet-Bulb, 



42 -7 

 41-3 



42-5 

 40-9 



43-3 

 41-5 



46-6 

 44-5 



51-2 

 48-4 



56-3 

 53-3 



57-8 



55-:; 



58-0 

 55'4 



55-4 

 52-9 



49-7 

 46-9 



45-8 

 43-9 



43-4 

 41-5 



49-4 

 47-1 



Difference, 



1-4 



1-6 



1-8 



2-1 



2-8 



3-0 



2-5 



2-6 



2-5 

 50-5 



84 



28 



1-9 

 41-7 



1-9 

 39-2 



2-3 



Dew-Point, 



39-6 



39-0 



39-4 



42-1 



45-5 



50-5 



53-0 



53-1 



S4 



439 



80 



- 



Percentage- ) 

 Humidity, I 



89 



88 



86 



S4 



80 



81 



84 



85 



85 



- 



Blacksod Point, 



Valencia, 



Markree Castle, Sligo, . 



Annual Humidity = 83-0 °/ 

 = 84-5 ,, 



