THE CLIMATE OE IRELAND. 41 



31 depression-centres crossed the British area during the past two years, 

 I goo and 1901, distributed according to the following Table : — 



Jan. Feb. Mar. Apr. May June July Aug. Sep. Oct. Nov. Dec. 



1900 6 '^3 3 



lOOi 5 3 4 5 



from which it will be perceived that cyclones have been much more pre- 

 valent in the winter half year. Disturbance was caused in the British area 

 by some twenty other cyclones, which crossed by the north-west, east, and 

 south. It was also found that the compass of the storms varied in diameter 

 from 200 to 2,400 miles ; and that, while most came from the west, some 

 twenty-five appear to have developed in the western European area, between 

 parallels of 47 and 65, and meridians 12 W. and 5 E. of Greenwich, and 

 some thirteen broke up within the same area. 



With respect to the commonly accepted " Equinoctial Gales," Mr. Rupert 

 Smith, from records for 26 years, ascertained that " cyclonic winds occur 

 with greatest frequency and force, some two weeks before the Spring 

 Equinox, and three weeks after the Autumn Equinox." 



From these circumstances it will be seen that winds in the Irish region 

 may w^ell greatly vary both in direction and force. Dr. Lloyd, in his report 

 on the Meteorology of Ireland,* has given a Table setting forth the directions 

 of wind, which shows that westerly winds are on the whole more than twice 

 as prevalent as easterly, throughout the year ; that the most frequent are 

 those from the S.W., W., and N.W. ; that the least frequent are east winds ; 

 and that south winds are the most prevalent after the westerly. 



Air takes up moisture at all temperatures, and becomes highly charged 

 when moving over sheets of water, marshes, and peat 

 Atmospheric bogs. It is, however, seldom charged to the full ex- 

 Moisture, tent that it will bear— it is seldom saturated. The 

 less moisture it contains, the greater its drying power, 

 or hygroscopic capacity, and the less is its " relative humidity." This term, 

 given in Meteorological Tables, maybe explained as the percentage of vapour 

 in the air to that which is necessary for its saturation. The greater the 

 relative humidity, the better it is for agriculturists at times when, as in May 

 and June, in Ireland, herbage is likely to suffer from drought through lack 

 of disturbance in atmospheric conditions, such as is usually attended by 

 rain. The average relative humidity for the year, reckoned upon monthly 

 averages for sixteen Irish Stations,! as given by Dr Lloyd, was as high as 

 87 per cent, for the year 1851. 



* Transactions of the Royal Irish Academy, vol. xxii., pp. 440-442. 



t It is not satisfactory to notice that while progress in meteorological, as in other scientific 

 observations, marks the present day, Ireland should be far behind, if it does not, even in some 

 particulars, show absolute as well as relative retrogression. 



While England and Wales have 47 Stations of tlie First and Second Order, and Scotland 25, 

 Ireland has only ^—five outside of Dubhn. Of Telegraph Reporting Stations connected with 

 the Meteorological Office, for preparation of Weekly Weather Reports, bearing upon Agricultural 

 and Sanitary matters, England has eleven or twelve, Scotland seven, Ireland five — the countries 

 being divided into six, three, and tjfo Districts respectively. In Rainfall Stations Ireland 

 unfortunatel).- shows the same strong disparity, it has but 146, against 249 in Scotland, and 

 2,802 in England and Wales. The United States is divided into eleven Districts, and has 77 

 Stations, recording temperature and rainfall, all linked together by means of the most elaborate 

 system of telegraphic communication. 



