It is certain, however, that in the ninth and eighth centuries this people used iron more freely than any other nation of the time. Thus several objects which appear at the first glance to be of solid bronze have an iron core within a more or less thin sheath of the other metal. Dr. Birch called my attention to numerous examples of this manufacture at the British Museum, in fragments of handles, of tires and various implements and utensils, from Kouyundjik and Nimroud. The iron could be distinctly seen at the fractures. The Assyrians clung to the bronze envelope because that metal was more agreeable to the eye and more easily decorated than iron, but it was upon the latter substance that they counted to give the necessary hardness and resistance. The contact and adhesion between the two metals was complete. From this, experts have concluded that the bronze was run upon the iron in a liquid state.[384] It is easy enough to understand how the inhabitants of Mesopotamia came to make such an extensive use of iron in the instruments of their industry; it was because they were nearer than any other nation to what we may call the sources of iron. By this we mean the country in which all the traditions collected and preserved by the Greeks agreed in placing the cradle of metallurgy--the region bounded by the Euxine, the Caucasus, the Caspian, the western edge of the tableland of Iran, the plains of Mesopotamia, the Taurus, and the high lands of Cappadocia. To find the deposits from which Nineveh and Babylon drew inexhaustible supplies, it is unnecessary to go as far as the northern slopes of Armenia, to the country of the Chalybes, the legendary ancestors of our mining engineers. The mountains of the Tidjaris, a few days’ journey from Mossoul, contain mineral wealth that would be worked with the greatest profit in any country but Turkey.[385] Bronze was reserved for such objects as we should make of some precious metal. Botta and Place found numerous fragments of bronze, but it is to Layard that we owe the richest and most varied collection of bronze utensils. It was found by him in one room of Assurnazirpal’s palace at Nimroud.[386] The metal has been analysed and found to contain ten per cent. of tin, on the average.[387] These proportions we may call normal and calculated to give the best results. In one of the small bells that were hung to the horses’ necks the proportion was rather different; there was about fifteen per cent. of tin. By this means it was hoped to obtain a clearer toned and more resonant alloy. Pure copper seems to have been restricted to kitchen utensils, such as the large cauldrons that were often used as coffers in which to keep small objects of metal, like the little bells of which we have spoken, rosettes, buttons and the feet of tables and chairs not yet mounted, etc.[388] It is probable that these vessels were also used for heating water and cooking food.