"There!" he said, as he placed it before Spolger, triumphantly.
"I know that bottle. But what has that to do with this murder?"
"Melstane died from morphia."
"It's no good going over the old ground," said Spolger, with a scowl. "I can easily prove my innocence. Please touch that bell, Mr. Axton."
Roger did so, whereupon a shrill sound rang through the house, and Mr. Spolger dropped back into his chair with an expression of acute suffering on his face. Then Gimp made his appearance with such marvellous rapidity that it was quite plain that he must have been listening outside the door, but he walked into the room with the utmost composure, and waited to be addressed.
"Gimp," said his master, sharply, "do you remember the day Mr. Melstane called?"
"I do, sir."
"Do you remember what took place?"
"Certainly, sir."
"Then tell these gentlemen all about it."