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reference to this subject of rainfall in India, and there is, perhaps, no other 
country in the world where its importance is more felt ; but I am afraid I 
should weary you. There is, however, one that is of peculiar interest 
to me, and that is the question of health. There is no doubt that the 
rainfall has a most marked effect on health. Those who have had to do, as 
I have, with the sanitary returns of India, and who have seen how im- 
mensely the fluctuations of disease, the spread of epidemics, the increase and 
decrease of such diseases as cholera, are influenced by the rainfall, will 
recognise that in India this matter of rainfall is of the greatest importance. 
I do not say that the disease I have mentioned is due to the quantity of 
rainfall ; but that the rain has a material and appreciable influence in 
originating, increasing, or diminishing the amount of epidemic disease, is, I 
say, beyond a doubt. Epidemic cholera is almost certain to diminish, if 
not altogether to die out, when the rains become heavy ; and it is equally 
certain that where the heat and evaporation are great, and the air dry, 
epidemic cholera, being present, it will spread and increase. I would not say 
that the increase or decrease of epidemics is due to rain alone ; but I would 
say that this is one cause which, combined with others, exercises potential 
influence, especially in the case of fevers. You will hardly believe me when 
I tell you of the amount of death from fevers in India. They destroy more 
than any other disease, and, compared with them, cholera is a mere cypher ; 
many other forms of disease may be immensely influenced by climate. When 
the season is dry and the evaporation is great, fevers diminish, that is to say, 
for a time ; but the effects of climate, whether the weather be dry or rainy, are 
not immediate , and the result of an accumulated or heavy and continuous rain- 
fall is always to increase and intensify the amount of deaths from fever. Only 
the other day I was looking at some returns on this very subject, sent to 
me from the Army Sanitary Commission, and I found that the increase in 
a number of diseases during the dry season was great. In fact, it is known 
to everybody living in India that the time of danger from climatic fevers is 
not when the rain is on the ground, but when the drying-up takes place : 
it is then that fevers abound. Then, as to the question of vegetation. Not 
only is the botanical part of this question, one having reference to the plants 
themselves, of interest, but that which materially concerns the climate is of 
great importance : not only is vegetation regulated by the rain, but the rain 
is regulated by vegetation. Many parts of Europe have become dry and arid 
and desiccated and depopulated, or very nearly so, by the destruction of the 
vegetation. This is because the vegetation being destroyed and the trees 
gone, the rain ceases to come ; it is no longer attracted there, and the con- 
sequence is that the face of the country is entirely altered. In Scinde and 
the Punjab, where vegetation is defective, though we have not found the 
districts rainless, yet the fall is defective, whilst at Mooltan there is but 
10 inches of rainfall in the year, which is not sufficient to supply the 
wants of the people. It is a well-known fact, that wherever vegeta- 
tion is increased it brings moisture : not very long ago, in passing 
through the Suez Canal, I observed that, in that dry and rainless country, 
