A Reader, Crete, Neb.—The greater weight of a body at the poles, as compared with its weight at the equator, is attributed, principally, to two causes, viz., the estimated shorter distance from the pole to the center of the earth; and the centrifugal force resulting from the revolution of the earth on its axis, which is zero at the poles and at its maximum at the equator.
John Steele, Chicago—Yes, a fine watch may easily be ruined by too close approach to a powerful electrical machine. The hair-spring and balance wheel become magnetized, and it is difficult and costly to get them demagnetized.
James McNulty, Chicago—The pitch of a roof is the ratio of its height divided by its span. Consequently a half pitch roof is one whose height is half its span, a quarter pitch one whose height is one-fourth the span, and so on. The answer you refer to was defective in omitting the word “span” after “foot.”
Charles Seymour, Chicago, Ill.—The Emperor Maximilian I., of Mexico, had two foreign legions besides his French allies, one known as the “Belgic Legion,” the other as the “Austrian Legion.”
O. Clark.—In the case of Wright vs. Wood it was decided that “four pre-emptors may combine to erect a house upon the corner common to their claims, but each pre-emptor must reside in his own part of the house.” If you will send your address and a postal-card we will answer your other question.