£ET. I.

OF ASTRONOMY.

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tinually increasing, the study of Geography, anda knowledge of the globe, became a necessarypursuit.

This science, as well as that of Navigation,was for a long time extremely imperfect and illunderstood: the knowledge of distant coun-tries was founded merely upon the vagueand uncertain accounts of travellers, who dis-figured and exaggerated all their relations bythat love of the marvellous, which is so naturaland congenial to the human mind: the pilot, onthe other hand, confined himself to the passingof narrow seas, or coasting along the ssiore, andpresumed not, by any dependance upon his art,to lose sight of land, and commit himself to tiremercy of the winds and waves. It was Astro-nomy that first inspired him with this confidence,and taught him to conduct his vessel, withsafety, through immense oceans, which hadnever before been traversed by man.

In this difficult and hazardous enterprise, it isnot sufficient for him to know the position ofthe port he designs to visit; he must also beable, at all times, to find upon what part of theglobe he is, how far he has travelled, and whatcourse he must pursue during the rest of hisvoyage. But these particulars can only beknown from astronomical observations, and anaccurate knowledge of the celestial motions.All the rules of the art are derived from this

source,