Billy did. So the two "sampled" as carefully as for an assay test in the School of Mines at Rapid. About half of the result Lafond exhibited as he had suggested, but the rest he preserved carefully for assay tests of his own.
To be sure, Billy had quite freely shown him his own official tests made at the School of Mines, but Lafond wanted his information more direct. He could not doubt the accuracy of the reports. But there was always a possibility that the sampling had not been fairly done. He was sure of these other "averages," for he had helped take them. He liked to have things under his own eye, and it was for this reason he had first suggested to Durand that he would like to take lessons in the art of assaying.
At first he had intended to use the old entomologist merely as a convenience, but later, as he became more intimate with the man through his work, he actually began to entertain for him a friendship—his first in over fifteen years. With all men he had been friendly; with none had he been friends. Here he proved a really generous emotion, opening his heart to the soft influences of affection and memory, allowing himself in this one instance an intimacy absolutely without ulterior motive. It all dated from the first day, when a chance question of Durand's touched the springs of the half-breed's youth.
They had adjourned that afternoon to the workshop, where Durand built a charcoal fire in a little furnace and gathered about him a choice assortment of curious implements. After the furnace was well heated, he roasted the ore Lafond had brought with him, heating it through and through, until finally the fumes of sulphur, antimony and arsenic ceased to arise from the chalk-lined iron basin. While the process was going forward Durand explained pleasantly the various steps of the chemical change, interspersing much extraneous information—as, for instance, how Winkler, Tcheffkin and Merrick claim that there is here a loss of gold, which Crookes denies—to all of which Michaïl Lafond lent but an inattentive ear. He was little interested in theory; but observing the old man's delight in the scientific aspect of the experiment, he feigned corresponding pleasure on his own part.
Then they spread a flux of granulated lead over a crucible, in appropriate juxtaposition with the roasted ore. For nearly two hours it was fused; and as there was nothing to do until the slag of impurities had formed about the bright metal in the centre, the men talked much to each other while waiting.
When the ore was completely fused, Durand seized the result in a pair of forceps. With a small hammer he broke away the great masses of clotted slag. A small bright metal button remained.
"This is the lead, the silver and the gold," explained Durand, "and it is here that we exercise care. All else is as child's play."
He flattened the button on an anvil, and cut it into several pieces. These he placed in the little porous vessels made of compressed bone ash, called cupels, which had been slowly heating in the furnace. The surface of the lead filmed over. In a moment it turned bright. Then fumes began to arise.
Durand's attention became fixed. His hand was constantly at the furnace valve, admitting or excluding more air according as he desired the temperature to rise or fall.
"It is this which is difficult," he explained from the corner of his mouth. "If the heat is too great, some precious metal escapes with the lead. If the heat is too little, the lead is not all driven away."