362 



Scientific Proceedings^ Royal Dublin Society. 



this amouut i.s collected, the day must be reckoned as rainy; and wlieu less 

 than half is observed, the water is tlirown away, and no rain registered. 

 The personal equation enters largely in deciding in cases of such small 

 quantities. In stating the average number of rain days per annum, the 

 estimate was given only to the nearest 5 in the units' place. 



'i'he following tables give particulars of position of gauge, duration of 

 record, values of mean annual rainfall and average number of rain days per 

 year, for tlie more important stations in the area studied, and also for a few 

 stations outside the area, tlie records of wliich were used as references. 



Table I. — Mean Annual Rainfall of Dub/in. 



