Volume 1
Yellow fever : considered in its historical, pathological, etiological, and therapeutical relations. Including a sketch of the disease as it has occurred in Philadelphia from 1699 to 1854, with an examination of the connections between it and the fevers known under the same name in other parts of temperate, as well as in tropical, regions / By R. La Roche.
- René La Roche
- Date:
- 1855
Licence: Public Domain Mark
Credit: Yellow fever : considered in its historical, pathological, etiological, and therapeutical relations. Including a sketch of the disease as it has occurred in Philadelphia from 1699 to 1854, with an examination of the connections between it and the fevers known under the same name in other parts of temperate, as well as in tropical, regions / By R. La Roche. Source: Wellcome Collection.
Provider: This material has been provided by Royal College of Physicians, London. The original may be consulted at Royal College of Physicians, London.
95/680 page 39
![sylvania Hospital, show that the annual average in a series of 25 years was 43.76.' This places Philadelphia on the same footing as most of the favoured cities of Europe, and higher than others, and many of those of this country ; but, as will be seen in a subsequent chapter, much below, on the point in question, other parts of this country, the West India Islands, some parts of the East Indies, the coast of Africa, &c. It may be added, in illustration of the variableness of our climate, that the summer and autumnal seasons arc sometimes characterized by an excess and at other times by a deficiency in the quantity of rain. Droughts of months’ duration are not uncommonly noticed, or shorter spells of dry weather, alter- nated with heavy showers or torrents, sometimes without, though generally with thunder.^ At other times, prolonged spells of rain, extending to a week or even to near a fortnight, and then, after intermitting with short periods of clear and dry weather, returning and continuing for some time longer, deluge the earth and injure the crops. At other times, again, rain falls in greater or less abundance during six, twelve, or twenty-four hours, and is followed by a few hours or a day or two of fine weather. This again is succeeded by rain, and the alternation continues for some time. The greatest quantity of rain sometimes falls in April, May, June, July, and August, or in December, and even in January. These last two occur- rences, however, are rare; the former are the most frequent—the spring or summer being often the wettest season of the year. A series of observations, covering a period of eight consecutive years, 1841 to 1848, shows that, during the three months of January, February, and March, rain fell to an amount varying from 6.21 inches to 13.78, with an average of 10.36. In April, May, and June, the amount varied from 5.29 to 14.55, with an average of 9.78. July, August, and September exhibited a variation of from 6.80 to 18.74, with an average of 12.58 ; while the amount in October, November, and December, varied from 8.35 to 13.31, with an average of 10.90. The average of the whole year being 43.62, and that of each of the four quarters 10.15.^ From the records of the rain-gauge kept at the Health Office, in a central part of the city, from March 1820, to February 1827, inclusive, the three months of winter averaged 8.15; spring, 8.29; summer, 9.54; and autumn, 10.54.“' Another series of observations made at the Pennsylvania Hospital, already referred to, gives for a period of twenty-five years the following averages;— January 3.23 ' April 3.26'] July 4.29] October 3.30] February 2.83 ^9.78 May 3.53 V 10.70 August 4.34 .11.93 Nov. 3.53 V 10.76 March 3.72^ June 3.91 J Sept. 3.30 J Dec. 3.93 J During the aforesaid period of eight years, the number of rainy days varied from 74 to 104; the whole amount being 724, with an average each year of 90.5. The number of cloudy days varied from 58 to 127, with a total ' Sum. of the Col. of Phys., N. S., ii. p. 168. 2 Rush, ii. 16, 17. 3 Sum. of the Col. of Phys., i. and ii. * Emerson, Am. Med. J., i. p, 120. L](https://iiif.wellcomecollection.org/image/b24990917_0001_0095.jp2/full/800%2C/0/default.jpg)
