He stood motionless, with his eyes fixed before him, and muttered in short sentences:
"Yes, that's it.... It's all clear now ... the explanation staring us in the face.... Why, of course, I knew it only needed a little thought!... Ah, my dear Wilson, this will rejoice your heart!"
And, leaving old chap where he was, he rushed into the street and ran to No. 25.
One of the stones above the door, on the right, bore the inscription: "Destange, architect, 1875."
The same inscription appeared on No. 23. So far, this was quite natural. But what would he find down there, in the Avenue Henri-Martin?
He hailed a passing cab:
"Drive to 134, Avenue Henri-Martin. Go as fast as you can."
Standing up in the cab, he urged on the horse, promising the driver tip after tip:
"Faster!... Faster still!"
He was in an agony as he turned the corner of the Rue de la Pompe. Had he caught a glimpse of the truth?