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that as Berlin is more than 13 degrees east of Green-wich, observations made on the moon when in themeridian, at Cape Town and at Berlin , are morenearly simultaneous than corresponding observationsat Cape Town and Greenwich.
Burg, by comparing Lacaille’s observations withthose made at Greenwich, deduced for the moon’sparallax the value 57' 1", corresponding to a distanceof 238,937 miles.
Henderson, the first who determined the distanceof the celebrated star Alpha Centauri , made a seriesof lunar observations at the Cape of Good Hope in1832 and 1833, with very imperfect instrumentalmeans. From a comparison of these observationswith others made at Greenwich and Cambridge, hededuced 57' 1"’8 for the value of the moon’s parallax.The corresponding distance amounts to 238,881 miles.
The Astronomer Royal, from a discussion of thewhole series of Greenwich observations, deduced thevalue 57' 4"‘94, corresponding to a distance of 238,656miles.
But probably the most accurate value is that whichhas "been deduced by Professor Adams from a com-parison of Mr. Breen’s observations at the Cape ofGood Hope , with others made at Greenwich andCambridge. Professor Adams deduces for the lunarparallax the value 57' 2" - 7, corresponding to a dis-tance of 238,818 miles.
One other method of determining the moon’s dis-tance remains to be mentioned. It cannot, however,