The language of the inscription is the purest Biblical Hebrew. There is only one word in it--that rendered "excess"--which is new, and consequently of doubtful signification. We learn from it that the engineering skill of the day was by no means despicable. The conduit was excavated in the same fashion as the Mont Cénis tunnel of our own time, by beginning the work simultaneously at the two ends; and, in spite of its windings, the workmen almost succeeded in meeting in the middle. They approached, indeed, so nearly to one another, that the noise made by the one party in hewing the rock was heard by the other, and the small piece of rock which intervened between them was accordingly pierced. This accounts for the two _culs de sac_ now found in the centre of the channel; they represent the extreme points reached by the two bands of excavators before they had discovered that, instead of meeting, they were passing by one another.
It is most unfortunate that the inscription contains no indication of date; but the forms of the letters used in it show that it cannot be very much later in age than the Moabite Stone. Indeed, some of the letters exhibit older forms than those of the Moabite Stone; but this may be explained by the supposition that the scribes of Jerusalem were more conservative, more disposed to retain old forms, than the scribes of king Mesha. The prevalent opinion of scholars is that the tunnel and consequently the inscription in it were executed in the reign of Hezekiah. According to the Chronicler (2 Chr. xxxii. 30), Hezekiah "stopped the upper watercourse of Gihon, and brought it straight down to the west side of the city of David," and we read in 2 Kings xx. 20, that "he made a pool and a conduit, and brought water into the city." The object of the laborious undertaking is very plain. The Virgin's Spring, the only natural source near Jerusalem, lay outside the walls, and in time of war might easily pass into the hands of the enemy. The Jewish kings, therefore, did their best to seal up this spring, which must be the Chronicler's "upper water-course of Gihon," and to bring its waters by subterranean passages inside the city walls. Besides the tunnel which contains the inscription another tunnel has been discovered, which also communicates with the Virgin's Spring. But it is tempting to suppose that the most important of these--the tunnel which contains the inscription--must be the one which Hezekiah made.