NOTE 3.—­I can have no doubt of the genuineness of this passage from Ramusio.  Indeed some such passage is necessary; otherwise why distinguish between three days of desert and four days more of desert?  The underground stream was probably a subterraneous canal (called Kanat or Karez), such as is common in Persia; often conducted from a great distance.  Here it may have been a relic of abandoned cultivation.  Khanikoff, on the road between Kerman and Yezd, not far west of that which I suppose Marco to be travelling, says:  “At the fifteen inhabited spots marked upon the map, they have water which has been brought from a great distance, and at considerable cost, by means of subterranean galleries, to which you descend by large and deep wells.  Although the water flows at some depth, its course is tracked upon the surface by a line of more abundant vegetation.” (Ib. p. 200.) Elphinstone says he has heard of such subterranean conduits 36 miles in length. (I. 398.) Polybius speaks of them:  “There is no sign of water on the surface; but there are many underground channels, and these supply tanks in the desert, that are known only to the initiated....  At the time when the Persians got the upper hand in Asia, they used to concede to such persons as brought spring-water to places previously destitute of irrigation, the usufruct for five generations.  And Taurus being rife with springs, they incurred all the expense and trouble that was needed to form these underground channels to great distances, insomuch that in these days even the people who make use of the water don’t know where the channels begin, or whence the water comes.” (X. 28.)

CHAPTER XXI.

CONCERNING THE CITY OF COBINAN AND THE THINGS THAT ARE MADE THERE.

Cobinan is a large town.[NOTE 1] The people worship Mahommet.  There is much Iron and Steel and Ondanique, and they make steel mirrors of great size and beauty.  They also prepare both Tutia (a thing very good for the eyes) and Spodium; and I will tell you the process.

They have a vein of a certain earth which has the required quality, and this they put into a great flaming furnace, whilst over the furnace there is an iron grating.  The smoke and moisture, expelled from the earth of which I speak, adhere to the iron grating, and thus form Tutia, whilst the slag that is left after burning is the Spodium.[NOTE 2]

NOTE 1.—­KUH-BANAN is mentioned by Mokaddasi (A.D. 985) as one of the cities of Bardesir, the most northerly of the five circles into which he divides Kerman. (See Sprenger, Post- und Reise-routen des Orients, p. 77.) It is the subject of an article in the Geog.  Dictionary of Yakut, though it has been there mistranscribed into Kubiyan and Kukiyan. (See Leipzig ed. 1869, iv. p. 316, and Barbier de Meynard, Dict. de la Perse, p. 498.) And it is also indicated by Mr. Abbott (J.