The angle of the gnomon being equal to the latitude of the place, the few degrees either side of the Equator would necessitate such a small elevation that a horizontal dial would be of little help. Again, a vertical dial would show the time for only a very short portion of the year, since the dial plate would have to be almost parallel with the rays of the sun. Still, doubtless, records may yet be found that will testify to its existence, if not in ancient Egypt, in lands that felt Egyptian influence and benefited by their learning and wisdom. Theories are problematical and surmises are often without foundation, but I would indeed venture to think that it is more than possible that the sundial played some part in the rectification of the Babylonian calendar in 747 B.C., which took place about nineteen years before the accession of King Ahaz, in whose reign it was clearly alluded to. The oldest known dials at present are those of Grecian origin, and for the most part are of the hemicyclean form invented by the Chaldean Berosus, who lived about 340 B.C., and his particular shape and construction of dial was in use for centuries. Four of these sundials were discovered in Italy: one at Tivoli in 1746, another at Castel Nuovo in 1751, another at Rignano in 1751, and the fourth at Pompeii in 1762. It is thus evident that this form of sundial which was used by the Arabians (who gave great study to gnomonics) was popular also amongst the Romans. An interesting specimen of this form of horologe, which can now be seen in the British Museum, was found at the base of Cleopatra’s Needle in 1852. This dial is concave, and is made from a stone 16½ inches high by 17 inches wide, the depth of the bowl being 10 inches; the hours marked are the twelve unequal hours by which the Greeks divided up their day. This dial—by no means satisfactory—doubtless owed much of its popularity to its novel construction, and to the fact that it was more or less of a portable nature. But the knowledge that it was constructed 360 years after the known existence of the sundial (see Isaiah xxxviii. 8), leads us to surmise that other forms of dials were in use at the same time. It is a known fact that the ancients were familiar with declining dials, and the Tower of the Winds at Athens, which still exists, has on its walls, built in octagonal shape, no fewer than eight of this kind. And although the date of these dials is evidently of a later period than the actual building, they certainly belong to a very early time. However, the Greeks were, as we know, well versed in the art of dialling, and without doubt gave a lead in this study to other nations.