He walked swiftly round from one to the other, pausing only at the large one which looked from the hall onto the stable lane. This he opened and made a very careful examination of the sill with his powerful magnifying lens. “Now we shall go upstairs,” said he at last.
The banker’s dressing-room was a plainly furnished little chamber, with a grey carpet, a large bureau, and a long mirror. Holmes went to the bureau first and looked hard at the lock.
“It is a noiseless lock,” said he. “It is no wonder that it did not wake you. This case, I presume, contains the coronet. We must have a look at it.” He opened the case, and taking out the diadem he laid it upon the table. It was a magnificent specimen of the jeweller’s art, and the thirty-six stones were the finest that I have ever seen. At one side of the coronet was a cracked edge, where a corner holding three gems had been torn away.
“Now, Mr. Holder,” said Holmes, “here is the corner which corresponds to that which has been so unfortunately lost. Might I beg that you will break it off.”