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throughout the British Isles, excepting from the Isle of Man, where 
he says the returns are imperfect,—informed me last year that he 
considered the average annual rainfall of the British Isles to be 
thirty-seven inches. Now, in the mountainous districts of this 
county, frequently one hundred and sixty inches fall, and we 
consequently possess special advantages for supplying towns with 
water, and our attention has simply to be paid to the best methods 
of collecting it. 
One inch of rainfall amounts to 22,622 gallons per acre, 
and, therefore, multiplying 22,622 by 3734 (the average annual 
rainfall), we have 848,325 gallons of rain per acre annually. 
This is a considerable quantity, and if properly collected in country 
villages, would afford a good supply of wholesome water. The 
question is, How can this be collected in a pure state? 
Mr. H. S. Wallis, Mr. Shirley Hibberd, and others, have 
recently suggested the desirability of collecting the rain on the 
roofs of houses as a supply for general domestic and drinking 
purposes; but it is evident that before this suggestion can be 
adopted, additional methods must be used for preventing the 
pollution which at present exists in rain-water collected in this 
manner. No doubt, however, attention may with advantage be 
given to this question, for the cost of a general supply of water 
from a distant source is heavy on small isolated householders in 
tural districts, and a supply in this way is therefore not agreeably 
accepted. I believe Mr. Symons discussed this subject in his 
address on “Water Economy” before the Sanitary Institute. I 
have not yet seen it, but it is published in the pamphlet form by 
Stanford, of Charing: cross. 
Although rain-water collected in country districts and pre- 
vented from contamination by decaying vegetable matter, &c., 
must beyond doubt be of the highest degree of purity, yet the taste 
of it is familiar to us as being disagreeably “flat.” This is due to 
its being “soft,” and not aérated 3 but on that account it is not 
injurious, and this fault might be remedied. Moderately hard water 
is pleasanter to the taste, and often quite as wholesome, as soft water, 
So that within certain limits the hardness or softness of a water does 
