I had never used a fluorescent screen before and I must confess that I found the experience most uncanny. As I raised it before the parcel behind which was the glowing green bulb, the parcel became invisible but in its place appeared the shadow of a pistol the muzzle of which seemed to be inserted into a jar. There were some other, smaller shadows, of which I could make nothing, but which seemed to be floating in the air.
“Better not look too long, Mayfield,” said Thorndyke. “X-rays are unwholesome things. We will take a photograph and then we can study the details at our leisure; though it is all pretty obvious.”
“It isn’t to me,” said I. “There is a pistol and what looks like a jar. Do you take it that they are parts of an infernal machine?”
“I suppose,” he replied, “we must dignify it with that name. What do you say, Polton?”
“I should call it a booby-trap, Sir,” was the reply. “What you might expect from a mischievous boy of ten—rather backward for his age.”
Thorndyke laughed. “Listen to the artificer,” said he, “and observe how his mechanical soul is offended by an inefficient and unmechanical attempt to blow us all up. But we won’t take the inefficiency too much for granted. Let us have a photograph and then we can get to work with safety.”
It seemed that this part also of the procedure was already provided for in the form of a large black envelope which Polton produced from a drawer and began forthwith to adjust in contact with the parcel; in fact the appearance of preparedness was so striking that I remarked:
“This looks like part of a regular routine. It must take up a lot of your time.”
“As a matter of fact,” he replied, “we don’t often have to do this. I don’t receive many parcels and of those that are delivered, the immense majority come from known sources and are accompanied by letters of advice. It is only the strange and questionable packages that we examine with the X-rays. Of course, this one was suspect at a glance with that disguised handwriting and the special direction as to who should open it.”
“Yes, I see that now. But it must be rather uncomfortable to live in constant expectation of having bombs or poison-gas handed in by the postman.”