THE MOON AND EARTH.

Patea Mail, 13 February 1882, Page 3

THE MOON AND EARTH.

The first lecture of the session at the Midland Institute, Birmingham, was delivered by Dr K, S. Ball, Astronomer Royal for Ireland, on a “Glimpse through the Corridors of Time.” In the course of his remarks, the lecturer said :—While the day was gradually lengthening through the moon’s action on the tides, the earth reacted on the moon and drove it farther and farther away. The circle described by the moon was therefore gradually increasing, and thus the day was getting longer and longer as the moon was receding farther and farther. If they looked back to earlier periods, the moon must therefore have been closer and closer to the earth. The farther they went back, and at one epoch which he put at about 50,000,000 of years, the moon must have been very close to the earth, and then the day, instead of being twenty-four hours, would only 7 be three hours long, Tlie closer the moon was to the earth the more quickly it revolved ; and, looking back to that remote period, they 7 had the extraordinary state of things in which the earth was spinning round once in every three hours, and the moon rotating once in three hours also. At that time the earth was really a mass of semi-molten matter, and if the oceans were there at all they 7 were suspended in vapour round it. He showed that the nearer the moon to the earth the greater was the rise of the tide ; and he calculated that, when the moon was so near the earth, the tides must have been 216 times as great as at the present time. Rising 240 feet high, the tides would have washed over the whole of England.