By BISHOP WARREN.

All have noticed that the tables of distances, magnitudes, etc., as printed in “Studies of the Stars” and “Recreations in Astronomy,” do not in all cases agree. In the latest edition of “Studies of the Stars,” the tables have been made to correspond to those in the “Recreations.” The reason of the discrepancy is the fact that we do not absolutely know the distance of the earth from the sun, which distance is the golden reed with which we measure the city of God. We are seeking to determine this distance. To this end we have fitted out expeditions to observe the transit of Venus, and are now expending time and money most prodigally. The difficulties are alluded to, page 61 of the “Recreations”: “To mistake the breadth of a hair, seen at the distance of 125 feet would cause an error of 3,000,000 miles at the distance of the sun, and immensely more at the distance of the stars.” That accounts for the greater discrepancies in the tables as the objects measured are farther off. It is better to commit to memory the tables in the “Recreations,” as they are the latest.