XLVI ACCOUNT or the life and

but nothing, it is evident, can be obtained in thisway, which approaches to a regular and conned-ed detail of human improvement.

In this want of dired evidence, we are under aneceffity of fupplying the place of fact by conjec-ture; and when we are unable to afcertam bowmen have actually conducted themfelves upon par-ticular occasions, of confidering in what mannerthey are likely to have proceeded, from the prin-ciples of their nature, and the circumftances oftheir external fituation. In fuch inquiries , the de-tached faffs which travels and voyages afford us,may frequently ferve as land-marks to our fpecu-lations; and fometimes our conclufions a priori,may tend to confirm the credibility of lads, which,on a fuperficial view, appeared to be doubtful orincredible.

Nor are fuch theoretical views of human affairsfubfervient merely to the gratification of curiofity.In examining the hiftory of mankind, as well as inexamining the phenomena of the material world,when we cannot trace the procefs by which anevent has been produced, it is often of importanceto be able to fhow how it may have been producedby natural caufes. Thus, in the inllance whichhas fuggefted thefe remarks, although it is impoffi-ble to determine with certainty what the ftepswere by which any particular language was formed ,yet if we can lhow, from the known principles of