7 AUGUST 1926, Page 18

The study of Mass Clocks-an early form of sundials-would be

a new and interesting hobby, and also an inexpensive one, for there are few Mass Clocks in England, and those that there are cannot be collected, but only studied on the spot. Mr. Green's book on the subject (Sundials, S.P.C.K.) is interesting, but a little abstruse for the average reader. Perhaps, how- ever, the subject demands some calculations, and there are certainly people in existence who actually enjoy doing sums. The author makes an interesting suggestion that the country- man of to-day preserves a sense of time independent of watches.