Our erect attitude : an essay / by John Wilson, M.D.

  • Wilson, John, M.D.
Date:
1888
Catalogue details

Licence: Public Domain Mark

Credit: Our erect attitude : an essay / by John Wilson, M.D. Source: Wellcome Collection.

Provider: This material has been provided by The University of Glasgow Library. The original may be consulted at The University of Glasgow Library.

    14/18 page 14
    SUPPLEMENTARY NOTE. (Read at a Subsequent Meeting of the Society.) Mr. President and Members,—My essay on “Our Erect Attitude ” now appeal's in the Glasgow Medical Journal of this month. The synopsis and diagrams will remind you of its leading features. I hope I have been successful in guarding against two possible accusations which strike most people at the first blush of such a subject as this. 1st. That I have any wish to see human beings become quadrupeds; and 2nd. That I am so infatuated as to dream that had the construction of the human frame been committed to me it would have been, long ere this, perfection itself. The downward attraction of gravitation on the solid and fluid constituents of our bodies at sea-level is very great, and it is only slightly lessened at any attainable elevation. Such lessening is only in proportion to the inverse ratio of the squares of the two distances from the earth’s centre; the two distances being, 1st. That from sea-level to earth’s centre ; and 2nd. That from elevation above sea-level to earth’s centre. Accordingly, a person weighing 10 stones at sea-level would, on the summit of Mont Blanc (which is about 3 miles in perpendicular height) show (with a spring balance) a diminished weight to the extent of only \ lb. Thus— Let 4,000 miles represent the mean radius of the earth from centre to sea-level. Let 4,003 miles represent distance from earth’s centre to summit of Mont Blanc. Let 10 stones or 140 lbs. be the weight of body at sea-level. Then the. square of 4,003 miles is to the square of 4,000 miles, as 140 lbs. is to 139f lbs. Showing that the body is only \ lb. lighter at summit than at sea-level. I think that a small spring balance might be constructed, having a minutely divided scale with index, and attached to it a definite weight at sea-level, say 1,000 grs. This would indicate diminution of weight at various elevations, and also serve to adjust aneroid observations of height. Of course, any balance with scales and weights could be of no use for this purpose, as the contents of each scale would be equally influenced by gravitation at all elevations. 1,000 grains at
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