The climate of the United States and its endemic influences. Based chiefly on the records of the Medical Department and Adjutant General's Office, United States Army / By Samuel Forry.
- Samuel Forry
- Date:
- 1842
Licence: Public Domain Mark
Credit: The climate of the United States and its endemic influences. Based chiefly on the records of the Medical Department and Adjutant General's Office, United States Army / By Samuel Forry. Source: Wellcome Collection.
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![ve that falls upon any point of the earth’s surface, depending, as it does, upon the amount of evaporation and the prevailing winds, is very in- timately connected with the character of climate. As a general rule, the annual quantity imcreases in proportion as the equator is ap- proached, more especially in maritime localities, and places in which elevated tracts skirt the sea-coast ; and as regards the seasons, the greatest amount falls when the mean monthly temperature is highest. As this augmented quantity in warm maritime countries falls at a particular season and in a shorter space of time than in colder re- gions, the annual number of dry days, particularly in inland districts, is proportionally increased. On the contrary, in the cold or temper- ate maritime localities now under consideration, the rain, notwith- standing much less in annual quantity, descends much more frequent- ly, but in slighter showers; and hence, a ready explanation is afford- ed of the fact that the ratio of wet and foggy days on the great lakes and coast of New England, is so much higher than in the climates on the same parallels characterized as excessive. 2. Tue Mippie Division.—The numerical results furnished by this Division are, as in the Northern, presented in the condensed summary, Table [G], on the opposite page. It has not been deemed fitting to arrange these posts into the two classes of uniform and excessive climes, as the majority of them are of a mixed character. The first two are slightly under the influence of the Atlantic, whilst the south-western stations experience the powerful agency of the Gulf of Mexico. ‘The laws of climate de- veloped in the preceding Division, do not find so happy an illustra- tion in this one ; for as the physical causes act less prominently, the effects are less marked. As we proceed south, the seasons become, as a general rule, more uniform in proportion as the mean annual temperature increases. Fort Mifflin and Washington city do not properly pertain to either class, being in a measure under the influ- ence of the ocean; but as we possess no thermometrical observations made directly on ie Atlantic on the same parallel, we are unable to determine the difference of climate. Fort Mifflin, near Philadelphia, shows a greater contrast in the opposite seasons than any one of the following posts, viz., Brady, Sullivan, Preble, Niagara, West Point, Constitution, Wolcott, and Trumbull; and Washington city exhibits greater extremes than the three last named. Although the results given at Washington city fairly place it in the class of excessive climes, yet on following the same parallel westward, a still greater](https://iiif.wellcomecollection.org/image/b33288379_0060.jp2/full/800%2C/0/default.jpg)
