"And what is this metal like?" I asked, with much interest, for my archæological instinct instantly was aroused by hearing summed in these few words a matter of such momentous importance as the transition of a people to the age of metal from the age of stone.
"It is like this," Tizoc answered, simply, disengaging as he spoke a heavy bracelet from his arm, "only this remains in its natural state of softness. To be of great value it first must be made hard."
I had no doubt in my own mind as to what this metal was, but I knew that Rayburn, who was an excellent metallurgist, could pronounce upon it authoritatively.
"Is this gold?" I asked, handing him the bracelet.
"Certainly it is," he answered, in a moment--"and it seems to be entirely without alloy."
"Then your guess about the bright, hard metal that has been such a puzzle to us," I continued, "was the right one; it is hardened gold:" and I repeated to him what Tizoc had told me.
Rayburn was deeply interested. "Scientifically, this is a big thing, Professor," he said. "These fellows can give points to our metallurgists. But for our purposes, of course, what they've caught on to here has no practical value. Gold has got to come down a good deal, or phosphor-bronze has got to go up a good deal, before it will pay us to turn gold dollars into axle-bearings and cogs and pinions. But it's mighty interesting, all the same. Fusing with silicium would give a gold-silicide that might fill the bill for hardness; but I can't even make a guess as to how they do the tempering. Ask the Colonel what the whole process is, Professor. It will make a capital paper to read before the Institute of Mining Engineers at their next meeting."
As I turned to Tizoc to ask this question, I perceived that his regard was fixed upon something on the other side of the court-yard, and in his look most tender love was blended with a deep melancholy. Following the direction of his gaze, I saw that its object was a beautiful boy, a lad of twelve or fourteen years old, who was half hidden behind some flowering shrubs, and from this cover was peering at us curiously.
"It is my Maza--my little son," Tizoc said, as he turned and saw the direction in which I looked. And then he called to the boy to come to him. For a moment Maza hesitated, but when the call was repeated he came out from behind the screen of flowers and so towards us across the court-yard; and as he advanced I perceived that he was lame. In his face was the look of wistfulness which cripples so often have, and there was a rare sweetness and intelligence in the expression of his large brown eyes. In a moment I understood why it was that Tizoc resented so bitterly the abrogation by the Priest Captain of the custom that had permitted parents to buy back their crippled children, and so to save them from slavery; and a selfish feeling of gladness came into my heart as this light dawned upon me--for I knew that when we faced the danger that threatened us (a most real danger, for our coming into the valley was nothing less than a deadly blow at Itzacoatl's supremacy) we surely would find in Tizoc an ally and a friend.