1885.] JREVIEWS OF BOOKS. 383 



drying of the south-westerly winds in their passage across Irehmd, 

 before they reach Southern Scotland, explains this diminished 

 rainfall. Where the south-westerly winds, on the other hand, have 

 a clear passage through St. George's Channel and the Irish Sea till 

 opposed by the high mountain masses of the Lake District and 

 North and South Wales, the rainfall rises in these latter regions 

 above 80 inches. The highest average rainfall in the Lake District 

 is 185-96 inches at The Stye, which, so far as yet observed, is the 

 heaviest rainfall anywhere in the British Islands. The highest in 

 North Wales is 116-90 inches, at Beddgelert; and in South Wales, 

 96-18 inches at Ty-Draw-Treherbert. All these localities are, like 

 Ben Nevis Observatory, on high peaks above and unprotected by the 

 neighbouring mountain escarpments, and so rain-bringing winds 

 from every direction strike on them. It is probable that future 

 observations at Ben Nevis Observatory will not vary much the 

 present annual rainfall of 146-24 inches, the largest observed in 

 North Britain. The annual rainfall regions of 6 inches or upwards 

 are thin elongated ellipses surrounding most of the mountain masses 

 from Sutherland to South Wales, besides covering similar regions in 

 West Galway and Kerry. Over a fourth part of the surface of 

 England, of about half of Ireland, and rather more than half of Scot- 

 land, there is a rainfall of 40 inches annually or upwards. Indeed, 

 this is not reached along the whole east coast of Scotland and some 

 distance inland ; while it is exceeded on the east of Ireland, thus 

 showing the influence of the Atlantic and the winds which blow 

 from it on the " Green Isle." The influence of the British mountain 

 chains from Sutherland to the hilly ground of the south-western 

 counties of England on this region of rainfall is well marked on the 

 rain-map, while its extension in comparatively level plains in central 

 Scotland, such as those of Kinross-shire, should prominently affect 

 any scheme of Scottish afforestation. The smallest average annual 

 rainfall, varying from about 22'50 inches to 25-00 inches, extends 

 over the district from the Humber to the estuary of the Thames, 

 exclusive of the higher grounds of Lincoln and Norfolk, where the 

 rainfall exceeds 25 inches. To this is to be added a small patch in 

 the vaUey of the Thames from Kew to Marlow. In every other 

 part of the British Islands the rainfall rises above 25 inches. The 

 sum of Mr. Buchan's paper is, that the key to the distribution of the 

 rainfall is the direction of the rain-brino-ins: winds in their relation 

 to the physical configuration of the surface. This should conse- 

 quently dominate any schemes such as that recently proposed by 

 Professor Howitz, for Irish tree-planting by the square mile. In 

 the Green Isle the mountains are not grouped in ranges, but scattered 

 in isolated fashion throughout the country, so the whole of Ireland 



