The ever-working left hand applied a liquid-soaked sponge to blank sheets of paper. No writing came to view after the chemical reaction. Tiger Bronson’s secret correspondence — if it existed — was still undiscovered.
The hand glided across the desk and rested upon a small pasteboard box which contained a number of ordinary pins. The hand removed a pin. It was held upright between the thumb and the second finger. The sensitive forefinger slipped over the top of the large-headed pin.
Rapid activity followed. The pin was dropped on the desk. One by one the other pins were subjected to the same inspection.
Some were chosen; others were placed aside. Evidently the finger had detected some roughness on the heads of certain pins.
The rejected pins were replaced in the box. The left hand disappeared and came back. It laid a paper, a pencil, and a microscope upon the desk. The flashlight was set upon a book. The right hand took the microscope; the left held a pin upright.
Under the powerful lens, the head of the pin appeared magnified to many times its ordinary size. Seen through the glass, it revealed words — a short message, engraved upon the pinhead!
The message read:
Plant plates with Birch.
The hand copied this on the paper.
Another pin came beneath the microscope. Its words were: