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LEWIS EVANS'—ADDRESS : 
shadow-lengths for the hours of the day at different times of the 
year, and quotes from Theodosius (about a.d. 100) as follows:— 
u To find the time iff is necessary to measure your own shadow 
by moving forward foot before foot to the end of the shadow of 
your head.” This method of finding the time was a very old 
one, and one of the earliest allusions to it is found in Aristophanes, 
who, writing about b.c. 430, in one of his plays talks of “a ten- 
foot shadow ” in connection with the time of day. 
Fig. 3.— English Cylinder Dial. 
One objection to this method was that, although there was ample 
difference in the length of the shadows near sunrise and sunset, 
towards noon the difference was very small; hut in the earliest 
Roman portable dial this is rather less noticeable, as the shadow 
of a projecting arm is allowed to fall on a vertical plate, so that 
the variation in the length of the shadow is considerable even at 
noon. The dial in question, which is now in the Museum at Naples, 
is fashioned to resemble a ham (Fig. 1, p. 2) ; it was found in the 
