and that Mr. Britton is more or less a personal friend."
"By the way, how comes it that the cheques are at the bank? Why were they not returned to Jeffrey with the pass-book in the usual way?"
"I understand from Britton," replied Thorndyke, "that all Jeffrey's cheques were retained by the bank at his request. When he was travelling he used to leave his investment securities and other valuable documents in his bankers' custody, and, as he has never applied to have them returned, the bankers still have them and are retaining them until the will is proved, when they will, of course, hand over everything to the executors."
"What is the object of photographing these cheques?" I asked.
"There are several objects. First, since a good photograph is practically as good as the original, when we have the photographs we practically have the cheques for reference. Then, since a photograph can be duplicated indefinitely, it is possible to perform experiments on it which involve its destruction; which would, of course, be impossible in the case of original cheques."
"But the ultimate object, I mean. What are you going to prove?"
"You are incorrigible, Jervis," he exclaimed. "How should I know what I am going to prove? This is an investigation. If I knew the result beforehand, I shouldn't want to perform the experiment."
He looked at his watch, and, as we rose from the table, he said:
