DIAL. The invention of the sun-dial belongs most probably to the Babylonians. Herodotus affirms, that the Greeks derived from them the pole (supposed to mean the dial-plate), the gnomon, and the division of day into twelve parts (ii. 1o9). Vitruvius also ascribes the most ancient form of the dial, called hemicycle, to Bcrosus the Chaldean (ix. 9), though he probably means no more than that he introduced it into Greece. Certainly those Greeks to whom Vitruvius acribes inventions or improvements in dialling, can all be proved to have had communication, more or less remote, with the Chaldwans. The first mention in Scripture of the hour,' is made by Daniel, at Babylon (ch. iii. 6). The Greeks used the dial be fore the Romans ; and with regard to the Egyp tians there are no indications in the Sculptures to prove the epoch when the dial was first known in Egypt' (Wilkinson, Anc. Egyptians, vol. iii. p. The circumstances connected with the dial of Ahaz (2 Kings xx. rz ; Isa. xxxviii. 8), which is perhaps the earliest of which we have any clear mention, entirely concur with the derivation of gno monies from the Babylonians. Ahaz had formed an alliance with Tiglath-pileser, king of Assyria (2 Kings xvi. 7, 9) : he was a man of taste, and was ready to adopt foreign improvements, as appears from his admiration of the altar at Damascus, and his introduction of a copy of it into Jerusalem (2 Kings xvi. to). The princes of Babylon sent unto him to inquire of the wonder that was done in the land' (2 Chron. mail. 31). Hence the dial also, which was called after his name, was probably an impor tation from Babylon. Different conjectures have been formed respecting the construction of this instrument. The difficulty is to understand what is meant by the trm the degrees or steps of Ahaz.' They may mean lines or figures on a dial-plate, or on a pavement, or the steps to the palace of Ahaz, or some steps or staircase he had erected elsewhere (vid. Carpzov, Apparat.
Histonie. Crit. Lips. 1748, p. 352, etc.) The Sept. in Isaiah reads dvagaOliobs. Tor, orKou To° ra-rp6s coy, the steps or stairs of the house of thy father.' Josephus also says, steps or degrees in his house' (rintiy. x. 2. /). The Chaldce renders the passage in Kings, N'VV..112N, hour-stone,' and gives the same meaning to the stairs' (2 Kings ix. 13), and renders Isa. xxxviii. 8 by the shadow of the stone of hours,' Symmachus most certainly understood a sun-dial : Tip (TKLRY KaT 071 ?v 'I will cause to return the shadow of the degrees which (shadow) is gone down on the.dial of Ahaz :' and so Jerome renders it Horologium. On the whole, the dial of Ahaz seems to have been a distinct contrivance, rather than any part of a house. It would also seem probable, from the circumstances, that it was of such a size, and so placed, that Hezekiah, now convalescent (Isa. xxxviii. 21, 23), but not perfectly recovered, could witness the miracle from his chamber or pavilion : `Shall nri, the or this shadow,' etc. May it not have been situate 'in the middle court' mentioned 2 Kings xx. 4 ? The cut given below (No. 206) presents a dial discovered in Hindostan, near Delhi, the ancient capital of the Mogul empire, whose construction would well suit the circum stances recorded of the dial of Ahaz. It seems to have answered the double purpose of an observatory and a dial—a rectangled triangle, whose hypo thenuse is a staircase, apparently parallel to the axis of the earth, and bisects a zone or coping of a wall, which wall connects the two terminating towers right and left. The coping itself is of a circular form, and accurately graduated to mark, by the shadow of the gnomon above, the sun's pro gress before and after noon ; for when the sun is in his zenith he shines directly on the staircase, and the shadow falls beyond the coping. A flat surface on the to of the staircase, and a gnomon, fitted the building for the purpose of an observatory. Ac cording to the known laws of refraction, a cloud or body of air of different density from the common atmosphere, interposed between the gnomon and the coping of the dial-plate below, would, if the cloud were denser than the atmosphere, cause the shadow to recede from the perpendicular height of the staircase, and of course to re-ascend the steps on the coping, by which it had be fore noon gone down ; and if the cloud were rarer, a contrary effect would take place. (See Bishop
Stock's Translation of Isaiah, Bath, 1803, p. to9.) Such a building might also be called a house.' It agrees also with Adam Clarke's suppo sition, that the stairs' were really a dial,' and probably this very dial, on which, as being in the most public place, or rather on tate platform on the top of which they set Jehu, while they proclaim ed him king by sound of trumpet' (Commentary on 2 Kings ix. 13). Bishop Stock's speculation that the retrogression of the shadow might be effected by refraction, is supported by a natural phenomenon of the kind on record. On the 27th of March in, P. Romauld, prior of the cloister of Metz, made the observation that, owing to such a refraction of the solar rays in the higher regions of the atmosphere, in connection with the appearance of a cloud, the shadow on his dial deviated an hour and a half (Rosenmiiller). The phenomenon on the dial of Ahaz, however, was doubtless of a miraculous nature, even should such a medium of, the miracle be admitted ; nothing less than a divine I communication could have enabled Isaiah to pre-1 diet its occurrence at that time and place ; besides, he gave the king his own choice whether the shadow should advance or retire ten degrees. There seems, however to be no necessity for seek ing any medium for this miracle, and certainly no necessity for supposing any actual interference with the revolution of the earth, or the position of the sun. In the more distinct and ample account of it in 2 Kings, it is simply said that the Lord, at the prayer of Isaiah, brought the shadow ten degrees backward. The words vnvri mrim P1)9,vo -)ev in Is. xxxviii. 8, And the sun went back ten de grees,' are wanting in three of Dr. Kennicott's MSS., and originally in two of De Rosi's ; and the words The shadow of the degrees which is gone down in the sun-dial of Ahaz' are more cor rectly rendered on the margin degrees by or with the sun,' i.e., by means of the progress of the sun. The first b Otos in this verse is omitted in MS. Pachom of the Sept. Even if the mention of the sun be retained, as in Ecclus. xlviii. 23, it is only fair to understand the words in their popular sense, the solar rays, or such a recession of the shadow as would have been occasioned by an actual recession of the sun. Adopting the present state of the text, it is observable that what is called the sun in one part of the verse is called the shadow in the other. It is certainly as philosophical to speak of the sun returning, as it is of his setting and rising. Thus the miracle, from all the accounts of it, might consist only of the retrogression of the shadow ten degrees, by a simple act of Almighty power, with out any medium, or at most by that of refracting those rays only which fell upon the dial. It is not said that any time was lost to the inhabitants of the world at large ; it was not even observed by the astronomers of Babylon, for the deputation came to inquire concerning the wonder that was done in the land. It was temporary, local, and confined to the observation of Hezekiah and his court, being designed chiefly for the satisfaction of that monarch. It is remarkable that no instrument for keeping time is mentioned in the Scripture be fore the dial of Ahaz, B. C. 700 ; nor does it appear that the Jews generally, even after his period, di vided their day into hours. The dial of Ahaz was probably an object only of curious recreation, or served at most to regulate the occupations of the palace.—J. F. D.