1917.] THE RAINFALL OF GUERNSEY. 07 



In the table showing the distribution of rainfall over the 

 whole Island, it will be seen that St. Martin's Road is again 

 the station with the greatest fall. Only one other station 

 reached 31 in., the Forest. Two stations, the Grange and 

 Villiaze, were between 30 and 31 in. 



The station collecting the smallest total this year is Mont 

 Saint, which failed to reach 26 in. (25*8). There was thus a 

 difference of 6 in. between the highest and lowest. As this 

 station collects in the averages 85% of the maximum fall, and 

 this year has collected only 81% it has a smaller fall this year 

 than would have been expected of it. 



The Forest Stations, on the other hand, have 97 — 96% 

 instead of 94 and 91%. 



It is now thoroughly established that the rainfall dimi- 

 nishes from East to West, and that the difference between the 

 Town and Cobo is, in round numbers, 3 in., and that between 

 the Town and St. Peter's is 6 in. 



The table shows that the mean of the whole of the 

 stations is, this year 29*1 or 92%, a figure which agrees with 

 the average of the centre of the Island fairly well. As this 

 is true of the central line of the Island only it cannot be 

 used with the same accuracy as the ascertained proportional 

 falls resulting from actual observation. 



A map has been prepared which shows the distribution of 

 rainfall over the Island, which, being arranged in lines of 

 percentages, will enable the approximate rainfall of any part 

 of the Island to be found for any past year or series of years 

 and which will also show the average rainfall in any part of 

 the Island. 



It is unlikely that the main details of the map will 

 change as a result of future observations, but the details of 

 the lines, as affected by hills and valleys, hns still to be 

 determined. 



The most interesting feature of the map is the contour of 

 the line of maximum rainfall. This line passes through the 

 Fort, crosses the Hubits, to the Oberlands. It is as yet 

 uncertain if it reaches Mount Row and descends Mount 

 Durand into Victoria Road, or whether it crosses the Mount 

 Durand estate and descends the Pierre Percee ; valley in either 

 case the fact seems certain that the line does not reach the 

 Grange. The other lines are more or less concentric to the 

 line of maximum fall. 



It will be noticed that there are two stations which do not 

 conform to the general distribution. These are probably 

 influenced by local conditions such as exposure, presence of 



