There is a Rabbinical tradition that the sons of Tubal-Cain, taught by a prophet of the coming deluge, and unwilling that their father's arts should be lost in it to posterity, erected two obelisks of brass, on which they inscribed a record of his discoveries, and that thus the learning of the family survived the cataclysm. The flood subsided, and the obelisks, sculptured from pinnacle to base, were found fast fixed in the rock. Now, the twin pyramids of the Old Red Sandstone, with their party-colored bars, and their thickly crowded inscriptions, belong to a period immensely more remote than that of the columns of the antediluvians, and they bear a more certain record. I have, perhaps, dwelt too long on their various compartments; but the Artist by whom they have been erected, and who has preserved in them so wonderful a chronicle of his earlier works, has willed surely that they should be read, and I have perused but a small portion of the whole. Years must pass ere the entire record can be deciphered; but, of all its curiously inscribed sentences, the result will prove the same--they will all be found to testify of the Infinite Mind. CHAPTER X. Speculations in the Old Red Sandstone, and their Character.--George, first Earl of Cromarty.--His Sagacity as a Naturalist at fault in one Instance.--Sets himself to dig for Coal in the Lower Old lied Sandstone.--Discovers a fine Artesian Well.--Value of Geological Knowledge in an economic View.--Scarce a Secondary Formation in the Kingdom in which Coal has not been sought for.--Mineral Springs of the Lower Old Red Sandstone.--Strathpeffer.--Its Peculiarities whence derived.--Chalybeate Springs of Easter Ross and the Black Isle.--Petrifying Springs.--Building-Stone and Lime of the Old Red Sandstone.--Its various Soils. There has been much money lost, and a good deal won, in speculations connected with the Old Red Sandstone. The speculations in which money has been won have consorted, if I may so speak, with the character of the system, and those in which money has been lost have not. Instead, however, of producing a formal chapter on the economic uses to which its various deposits have been applied, or the unfortunate undertakings which an acquaintance with its geology would have prevented, I shall throw together, as they occur to me, a few simple facts illustrative of both.