It was a stickler.
I dropped in to see a writing expert, and after examining them, he said that the two specimens might or might not be written by the same person.
"It is penmanship as taught in our public schools," he said. "Pupils are drilled into a set way of forming their letters, as a consequence of which there is a great similarity in writing until the persons have been for years out of school."
That settled it.
The similarity was one caused by education, and I was more than ever convinced of Mat and Shadow being one individual.
I went home in a thoughtful mood.
There I found a letter awaiting me from the chief, asking why I had not reported in a certain matter which had been placed in my hands.
I felt conscience-stricken.
In my great interest in what concerned Shadow I had neglected my duty, to which the last few hours should have been devoted, instead of to an endeavor to find out whether Shadow was Mat Morris, or Nellie Millbank, or somebody else.
Immediately I donned the disguise in which I had acted a part, and wound my way into the confidence of Woglom and his companion, by means of which I had learned of the prisoner in the black hole.