Appendix to report of the committee for scientific inquiries in relation to the cholera-epidemic of 1854.

  • Great Britain. General Board of Health. Medical Council.
Date:
1855
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Licence: Public Domain Mark

Credit: Appendix to report of the committee for scientific inquiries in relation to the cholera-epidemic of 1854. Source: Wellcome Collection.

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    The numbers in the lowest line show the monthly diffei-ence of atmospheric pressure from the average in the year 1854. From them we learn that the pressure was in defect in Janiiary, May, June, and December; was near its average value in July and November, when it was slightly in excess ; it was in excess in all the remaining months. In February the excess was large, and the reading was greater than in any February in the series, except 1849. In March the excess was very large, and the reading exceeds that of any March in the above series. In April the excess was large, and the reading was exceeded in one instance only, viz., in April 1844. In August the excess was large, but there are three instances in the Table with readings of nearly the same value, viz., in 1842, 1849, and 1851. In September the excess was large, and the reading exceeded that of September in the series. The mean reading for the year 1854 was 30-021 inches, exceeding the average by 0'082 inches. Temperature of the Air. The thermometers employed in determining the temperature and humidity of the air were made by Messrs. IsTegretti and Zambra, and, as before stated, were all carefully compared with standards, and their errors determined. The mean daily temperature of the air was found from the mean of the observations of the dry-bulb thermometer, corrected for diurnal range ;* and a second mean was found from the readings of the maxi- mum and minimum thermometers, also corrected by a quantity given in the same paper. The adopted mean temperature for each day was then determined by combining these two values, and giving them weights proportional to the number of observations from which they respectively derived. The mean of these was taken weekly; their results are shown in the annexed Table. * The quantities required to perform these corrections will be found in a paper by myself, published in the Philosophical Transactions, Part I. 1848.
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