water of the margin of the stream becomes pellucid by standing in an open vessel over night, depositing its feculencies at the bottom. But the spring water, issuing through fissures in the hills, which are only masses of coal, is so impregnated with bituminous and sulphureous particles as to be frequently nauseous to the taste and prejudicial to the health.
We observed several people near Pittsburg affected with a tumour on the throat {46} like a wen. Inquiring into the cause of it, we were informed that they imputed it to some effect of the climate under the brows of the high mountains where they reside, and added that even dogs and some other animals were subject to it. Indeed we saw a couple of goats who had this uncomfortable appendage to their necks.
The Seneca Indian Oil in so much repute here is Petroleum; a liquid bitumen, which oozes through fissures of the rocks and coal in the mountains, and is found floating on the surface of the waters of several springs in this part of the country, whence it is skimmed off, and kept for use. From a strong vapour which arises from it when first collected, it appears to combine with it sulphureous particles. It is very inflammable. In these parts it is used as a medicine; and, probably, in external applications with considerable success. For chilblains and rheumatism it is considered as an infallible specific. I suppose it to be the bitumen which Pliny describes under the name of Naptha, Lib. II. ch. 105. {47} Tuesday, April 19
Crossed the ferry over the Monongahela, opposite the glass-houses, and pursued our journey.
The country is very mountainous and broken, and the
