He spread out the last of the mysterious letters, and we saw that, besides the memento mori, it contained only three words: "Beware! Remember Capri!"
"If you have finished, Doctor, I'll be off and have a look round Little Italy. Those four Italians oughtn't to be difficult to find, and we've got the porter here to identify them."
"Before you go," said Thorndyke, "there are two little matters that I should like to settle. One is the dagger: it is in your pocket, I think. May I have a look at it?"
The inspector rather reluctantly produced the dagger and handed it to my colleague.
"A very singular weapon, this," said Thorndyke, regarding the dagger thoughtfully, and turning it about to view its different parts. "Singular both in shape and material. I have never seen an aluminium hilt before, and bookbinder's morocco is a little unusual."
"The aluminium was for lightness," explained the inspector, "and it was made narrow to carry up the sleeve, I expect."
"Perhaps so," said Thorndyke.
He continued his examination, and presently, to the inspector's delight, brought forth his pocket lens.
"I never saw such a man!" exclaimed the jocose detective. "His motto ought to be, 'We magnify thee.' I suppose he'll measure it next."
The inspector was not mistaken. Having made a rough sketch of the weapon on his block, Thorndyke produced from his bag a folding rule and a delicate calliper-gauge. With these instruments he proceeded, with extraordinary care and precision, to take the dimensions of the various parts of the dagger, entering each measurement in its place on the sketch, with a few brief, descriptive details.