Climate and weather / by H.N. Dickson.

  • Dickson, H. N. (Henry Newton), 1866-1922.
Date:
[1912]
Catalogue details

Licence: In copyright

Credit: Climate and weather / by H.N. Dickson. Source: Wellcome Collection.

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    earth’s surface, and to compare their influences upon its different parts. The gain and loss of heat at the surface are of paramount importance. Leaving out of account, as observation shows we may safely do, the small amounts of heat received by conduction from the earth’s hot interior, we find that the only source of heat to be reckoned with is the sun. The sun does not itself give out heat, but it emits rays which are propa- gated as waves or ripples in the medium which pervades all space and is called the ether. These rays are of widely different wave-lengths, and some of them produce special effects when they impinge on specially prepared surfaces : thus some, falling upon the retina of the eye, produce impressions interpreted by the brain as light, and rays of different wave-lengths (within certain limits) give impressions of different coloured light, the aggregate of all the solar rays within the light limits giving the impression known as white light. Some rays, again, produce chemical effects upon certain compounds—