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ever except vapour which falls on the surface from the ocean. Chalk, sand, 
and some other of our geological strata are very absorbent, and to a great 
extent, though not entirely, they absorb the water which falls upon them. 
There are other measures, such as the primitive measures, including 
the granite, some of the slates and the millstone grit, where the country 
is very rugged, and where the great bulk of the water runs away and 
comparatively very little of it enters the surface of the ground. The conse- 
quence is, that in these districts there is very little spring water, while in the 
chalk and sand you have much spring water. In considering the quantity of 
the rainfall, and the useful purposes to which it may be applied, all these 
circumstances have to be taken into account. With regard to the reference 
made to the spots on the sun as bearing upon the rainfall, I believe that that 
is only a coincidence. There have been spots on the sun at all times, and I 
do not believe that these phenomena can have sufficient influence to affect 
materially the power of evaporation which acts upon the surface of the ocean, 
or the quantity of rain that falls. We have heard it stated that the felling 
of the timber in India has considerable influence on the climate, and that the 
droughts which have been suffered in that country are due to the destruction 
of the forests. We have had four or five uncommonly wet summers which 
may have been accompanied by spots on the sun, and the interference thus 
made with the sun’s usual surface may have affected its action ; but I can 
scarcely believe that the result is at all appreciable, and that if the sun has 
been thus affected, we can measure the extent of the interference. We are 
not yet in a condition to be able to determine any law as to the succession 
of droughts and wet weather. There are some districts which are rainless ; 
there are, as we have heard, others where there are 610 inches of rain, so that 
the rainfall in the latter is not 125 times the ordinary amount, but between 
500 and 600 times the average fall. Therefore I think that any calculations 
of the kind we have heard are as unstable add uncertain as the wind that 
blows, and which has so great an effect on meteorology. It may be that in 
some parts of the country the figures of the rainfall may be multiplied by 
themselves to produce the results met with in other parts. If you take 
10 inches on the east coast as against the 200 inches found on the west coast 
the one figure can be multiplied by twenty to produce the other ; and you 
cannot draw any conclusion from this beyond knowing that the figures have 
been taken for the purpose of multiplication. I do not believe we have any 
sufficient information at the present time to enable us to say that a period of 
frost or cold, — hardly a glacial period, — is followed by a period of wet. It 
may be, and it may in past times have been, that we have suffered from a 
glacial period at one time, and at another from a period of excessive rain and 
denudation, but we can only reason to a certain extent as to the past by what 
we see at the present time, by that of which we have some certain know- 
ledge. I have not in this paper endeavoured to speculate on the circum- 
stances I have adduced, but have merely narrated the facts, and I believe 
that the best way of promoting scientific investigation is to collect a number 
of absolute facts, and present them in their bearing on each other. A friend 
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