TRANSACTIONS OF SECTION G. 



733 



40 inches falls over tlie whole of Ireland west of the Foyle and the Shannon, and 

 to the west and south of a line drawn from Limerick through Mallow to Clonmel, 

 whence a narrow belt, equally wet, runs north-eastward through the counties of 

 Waterford, Wexford, and AVicldow. Two small areas with more than 40 inches 

 occur in the south-east of Co. Down and the east of Co. Antrim. .Vll the rest of 

 Ireland has between 30 and 40 inches of rain, except parts of Co. Dublin and 

 Co. Meath, where the fall averages less than 30 inches. The following table gives 

 a rough approximation to the areas of the different zones of rainfall :— 



Under 30 inches (average 29 in.) . 

 From 30 to 40 inches (average 35o in.) 

 From 40 to 50 inches (average 44 in.) . 

 Above 50 inches (average 60 in.) . 



Ireland 



700 square miles. 

 13,200 

 13,500 

 5,200 



32,600 



This gives an average of 42 inches for the whole country; a figure which, 

 althouo-h by no means certain, is probably not very far from the truth. 



The variations of rainfall in Ireland are less than those in England. Thus for 

 the ten years 1890-99 the rainfall over Ireland was only 2 per cent, below the 

 thirty years' average; that over England and Wales showed a deficiency of 7 per 

 cent.* The average rainfall of the ten years was practically the same as that of 

 the thirty years in central Ireland, a tritie above the average in the north-west, 

 and a littlebelow the average round the north, east, and south coasts. 



Rainfall Averages for Thirty Years, 1870- 



99. 



Place 



1870-79 . 1880-89 



Portlaw, Mayfleld, Co. Waterford 



Glenam, Clonmel, „ 



New Ross, Longraigue, Co. Wexford 



Enniscorthy, Ballyhyland, „ 



Gorey, Courtown House, 



Inistioge, Woodstock, Co. Kilkenny 



Bray, Fassaroe, Co. Wicklow 



Carlow, Browne's Hill, Co. Carlow 



Dublin, FitzWilliam Square, Co. Dubl 



Athlone, Twyford, Co. West Meath 



Ballinasloe, Co. Galway 



Tuam, Gardenfield (6 ft.). Co. Galway 



Belturbet, Redhills, Co. Cavan . 



Armagh, Observatory, Co. Armagh 



Seaforde, Co. Down . 



Banbridge, Milltown, Co. Down 



Waringstown, >. 



Belfast, Queen's College, Co. Antrim 



„ Antrim Eoad, „ 



Omagh, Edenfel, Co. Tyrone 



1890-99 



in. 

 41-65 

 43-47 

 43-57 

 44-36 

 38-14 

 46-64 

 38-70 

 36-09 

 28-47 

 40-47 

 38-89 

 38-43 

 36-57 

 30-95 

 41-67 

 32-75 

 .S4-03 

 34-92 

 33-86 

 37-25 



in. 

 43-31 

 4215 

 39-29 

 42-80 

 35-39 

 41-67 

 43-28 

 33-59 

 27-47 

 38-97 

 35-66 

 42-76 

 34-57 

 32-16 

 37-89 

 31-44 

 33-02 

 32-77 

 34-57 

 36-63 



in. 

 42-18 

 40-89 

 38-75 

 41-45 

 33-62 

 38-60 

 39-68 

 33-65 

 27-30 

 35 83 

 36-58 

 41-85 

 34-42 

 30-97 

 36-27 

 30 23 

 3414 

 3200 

 35-28 

 39-66 



1870-99 



m. 

 42-38 

 42-17 

 40-54 

 42-87 

 35-72 

 42-27 

 40-55 

 34-44 

 27-75 

 38-42 

 37-04 

 41-01 

 3519 

 31-36 

 38-61 

 31-47 

 33-73 

 33-23 

 34-57 

 37-85 



7. Water Power in Ireland. By F. J. Dick. 



8. 



A Direct Reducing Levelling Staff. 

 By G. W. Herdman, B.Sc. 



The object of this staff is to lessen the arithmetic which is always necessary 

 to obtain from the observation through the level telescope the actual height above 

 datum (or ' reduced level') of the spot where the staff is held. 



Iritish Rawfall, 1901, p. 24. 



tea 



