CLOCKS AND NOON-MARKS.
Danvers, Ill.
How many correct noon-marks can be made during a year?
H. M. Valentine.
Answer.—Four correct “noon-marks” are made in a year, on the following days: Dec. 24, April 15, June 14, and Sept. 1. Owing to the inclination of the earth’s axis and its unequal movement in its orbit, solar days vary in their length. The average solar day corresponds to the twenty-four hours of our clocks, which keep what is called mean time. If a clock were so constructed as to give the real solar time for all periods of the year, it would be observed that sometimes when the solar clock pointed at noon, the ordinary clock, keeping mean time, would be pointing at figures between 11:45 and 12, or at other times between 12 and 12:15. Four times each year, however, upon the days mentioned, the two clocks would coincide, and the shadow of a dial, or noon-mark, would point due south at noon by the clock.
THE FATHER OF THE HUMANE SOCIETY.
Bedford, Iowa.
Please give a short sketch of Henry Bergh, so long the President of the American Society for the Prevention of Cruelty to Animals.