AN ACCOUNT
OF THE
CLIMATE OF PENNSYLVANIA,
AND ITS
INFLUENCE UPON THE HUMAN BODY.
In order to render the observations upon the epidemic diseases which compose the following volumes more useful, it will be necessary to prefix to them a short account of the climate of Pennsylvania, and of its influence upon the human body. This account may perhaps serve further, to lead to future discoveries, and more extensive observations, upon this subject.
The state of Pennsylvania lies between 39° 43′ 25″, and 42° north latitude, including, of course, 2° 16′ 35″, equal to 157 miles from its southern to its northern boundary. The western extremity of the state is in the longitude of 5° 23′ 40″, and the eastern, is that of 27′ from the meridian of Philadelphia, comprehending in a due west course 311 miles, exclusive of the territory lately purchased by Pennsylvania from the United States, of which as yet no accurate surveys have been obtained. The state is bounded on the south by part of the state of Delaware, by the whole state of Maryland, and by Virginia to her western extremity. The last named state, the territory lately ceded to Connecticut, and Lake Erie, (part of which is included in Pennsylvania) form the western and north-western boundaries of the state. Part of New-York, and the territory lately ceded to Pennsylvania, with a part of Lake Erie, compose the northern, and another part of New-York, with a large extent of New-Jersey (separated from Pennsylvania by the river Delaware), compose the eastern boundaries of the state. The lands which form these boundaries (except a part of the states of Delaware, Maryland, and New-Jersey) are in a state of nature. A large tract of the western and north-eastern parts of Pennsylvania are nearly in the same uncultivated situation.
The state of Pennsylvania is intersected and diversified with numerous rivers and mountains. To describe, or even to name them all, would far exceed the limits I have proposed to this account of our climate. It will be sufficient only to remark, that one of these rivers, viz. the Susquehannah, begins at the northern boundary of the state, twelve miles from the river Delaware, and winding several hundred miles, through a variegated country, enters the state of Maryland on the southern line, fifty-eight miles westward of Philadelphia; that each of these rivers is supplied by numerous streams of various sizes; that tides flow in parts of two of them, viz. in the Delaware and Schuylkill; that the rest rise and fall alternately in wet and dry weather; and that they descend with great rapidity, over prominent beds of rocks in many places, until they empty themselves into the bays of Delaware and Chesapeak on the east, and into the Ohio on the western part of the state.
The mountains form a considerable part of the state of Pennsylvania. Many of them appear to be reserved as perpetual marks of the original empire of nature in this country. The Allegany, which crosses the state about two hundred miles from Philadelphia, in a north, inclining to an eastern course, is the most considerable and extensive of these mountains. It is called by the Indians the back-bone of the continent. Its height, in different places, is supposed to be about 1,300 feet from the adjacent plains.
The soil of Pennsylvania is diversified by its vicinity to mountains and rivers. The vallies and bottoms consist of a black mould, which extends from a foot to four feet in depth. But in general a deep clay forms the surface of the earth. Immense beds of limestone lie beneath this clay in many parts of the state. This account of the soil of Pennsylvania is confined wholly to the lands on the east side of the Allegany mountain. The soil on the west side of this mountain, shall be described in another place.
The city of Philadelphia lies in the latitude of 39° 57′, in longitude 75° 8′ from Greenwich, and fifty-five miles west from the Atlantic ocean.