The Coming Transit of Venus ^†

Abstract

IV.

IT has already been pointed out how unsatisfactory in 1 some respects were the results of the observations made in 1761. Those of the year 1769 were more suc-1 cessful, but the discrepancies of different observers still threw a doubt on the result. After Encke had discussed with all possible care the observations made upon these two occasions,! doubts were still raised as to the correctness of the value thus found for the solar parallax. The reasons of these doubts were manifold. In the first place in order to get any value whatever of the solar parallax, Encke had been forced to assume that enormous errors had been committed by some of the observers; and again, all the other methods of which we have spoken were found to give a tolerably accordant value of the solar parallax, but values that differed considerably from Encke's determination.