The volcanic origin of epidemics / by John Parkin.

  • John Parkin
Date:
1887
Catalogue details

Licence: Public Domain Mark

Credit: The volcanic origin of epidemics / by John Parkin. Source: Wellcome Collection.

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    which, therefore, were particularly exposed to the influ- ence of the wind, suffered more than any others. As the influence of the wind, in this instance, is self- evident, what, we may ask, was the occult cause of these different effects ? Dr. Clarke and others thought the phenomenon could be explained on the supposition, that the emanations in the back yards of the houses, on the windward side of the streets, that run perpendicular to the trade-wind, were driven into these houses; while they were unable to enter, or were driven away from, the houses on the opposite side. These conclusions might be satisfactory enough, provided only it were shown that such emanations are sufficient to produce the effects under consideration; but that cannot be the case, if my pre- vious deductions be of any value. Such an explanation, - avain, would be sufficient to account for the result observed in the other streets—those that run parallel to the wind. As in these instances the wind must have blown over the backs as well as the fronts of the houses, there would necessarily have been an accumulation of the emanations from the yards at the leeward end of these streets : where also the mortality, according to the above hypothesis, ought to have been the greatest. The con- trary, however, is the fact: the mortality, as we have seen, being actually 5T per cent, less at the leeward than at the windward extremity of these streets. The eman- ations from the yards could not, therefore, have been the cause of the variations observed in the mortality of these different streets. Besides, we have observed the same phenomenon in other situations where this cause was not in operation. In London, during the outbreak of cholera, in St. James' parish, in 1854, it was remarked,
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