A paper on the influence of clays and limestones on medical geography : illustrated by the geographical distribution of cancer among females, in England and Wales / by Alfred Haviland.

  • Haviland, Alfred, -1903.
Date:
1891
Catalogue details

Licence: Public Domain Mark

Credit: A paper on the influence of clays and limestones on medical geography : illustrated by the geographical distribution of cancer among females, in England and Wales / by Alfred Haviland. Source: Wellcome Collection.

Provider: This material has been provided by The Royal College of Surgeons of England. The original may be consulted at The Royal College of Surgeons of England.

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    are rendered deeper and deeper. Again, the joints of the lime- stone slabs are eaten away in a similar manner, so that they are now wide enough to admit a man's leg in many places, and the gaping chasms render great caution necessary in walking over this weird sculptured pavement. It is evident from what has just been described that the limestone has neutralised the acids that have been formed by the vegetable decomposition, which first took place at the surface of the slabs; and that the drainage of the carbonated rain water, rendered more acid by vegetable de- composition, first marked out the courses of the flowing acid water, so in the sequel were these courses preserved until, by gradual deepening, they were able to afford shelter to the blown leaves that fell from the trees around, until they were piled up in rotten masses of acid-forming material. The great lesson that this interesting locality teaches us is that one of the chief functions of limestone is to neutralise the acid products of vegetable decomposition, and that this func- tion is more or less well fulfilled whenever it is required; that it matters not whether the evil to be counteracted arises from a mass of dead leaves lying sodden on its surface, or from the results of a widespread flood covering many square miles. I will now give you the facts which have, in my opinion, a special bearing on the influence of Clays and Limestones on the geographical distribution of cancer among females as an illus- tration of the subject. (i) The Thames Basin. In 1868 I constructed the map that I now exhibit, show- ing the geographical distribution of cancer among females at all ages during the ten years 1851-60. In that map you will find that certain areas are coloured in different shades of blue, the darkest blue representing the highest death rate from this cause, whilst the other areas are coloured in different shades of red, the darkest red indicating the lowest death rates. In the Thames Basin there will be found five groups of districts which follow the river in its course, and are either bounded or traversed by it. The highest group (i) consists of districts below Oxford, more or less characterised by clayey soils and subsoils; superadded to which are alluvial clays and river gravels. This group consists of the following districts—Wallingford, Bradfield, Reading,