"But," Viantes suggested, "you might damage it. It might fly into a thousand fragments if it was subjected to a very intense cold. What of that, my lord?"
"Then, in that case, I shall be the loser," Rayburn smiled. "I should have to find that sum of money, which, between ourselves, would absorb my private means, because, when I die, this place of mine and my income must go to my successor. And my assistant would be all the poorer, which would be very hard upon him, seeing that he knows of my intentions, and that he is going to be married very shortly."
As Rayburn finished, he rose to his feet and, unlocking a drawer in his writing-desk, produced a great diamond. It was a magnificent stone, and as it lay winking and sparkling on the table, Viantes' eyes narrowed behind his spectacles, and his mouth quivered like that of a cat stalking a bird.
"A wonderful gem!" he murmured.
"Yes, a royal gem. Now, it was lent to me by a firm of Court jewellers for the purpose of my experiment. You must understand that it is what is called a superimposed stone—that is, two layers placed one upon another, and joined by spirit gum or something of that kind, much as they join a series of glasses from which telescopic lenses are ground. Originally the diamond was much bigger; but it met with an accident— a fracture in the centre—so that it was necessary to split the stone in two and join it up again. Of course, this detracted from the value, but only an expert could tell and discern the tiny spot of moisture that was created in the process. Now, my idea, as you know, is literally to burn out that moisture by frost, and therefore, in one of my tanks which lie out yonder beyond the conservatory, I propose to subject the stone to a freezing process a hundred degrees below zero; and when that is done, I am sanguine that the flaw will have vanished. If you have another half-hour or so to spare—"
The sentence was never finished, for the Spaniard was on to Rayburn like a flash, as the latter bent over the table, a knife gleamed in the air, and the great man collapsed to the floor, stricken between the shoulders to the heart, and lay there dead without a single sound.
* * *
It was nearly six o'clock before Hayter, feeling a little uneasy, knocked at the laboratory door without receiving any reply. He flew round to the back of the house, with the idea of approaching the laboratory by a flight of steps leading up to the big tanks with their concrete tops. The motor-car in the lane had disappeared, and this only added to Hayter's uneasiness. It was nearly dark now, so that Hayter noticed nothing except that the lid over the manhole of one of the great freezing tanks had not been slipped back, and this he hastily readjusted.
"I suppose I am to blame for that," he murmured. "Well, it doesn't so very much matter."
Just by the conservatory door lay a spray of three or four blooms of the priceless Gynandria Monandria. Hayter stooped and mechanically placed it in his buttonhole.