“It is sometimes possible,” he continued, “to decipher writing on burned papers if one is careful.  The processes of colour photography have recently been applied to obtain a legible photograph of the writing on burned manuscripts which are unreadable by any other known means.  As long as the sheet has not been entirely disintegrated positive results can be obtained every time.  The charred manuscript is carefully arranged in as near its original shape as possible, on a sheet of glass and covered with a drying varnish, after which it is backed by another sheet of glass.

“By using carefully selected colour screens and orthochromatic plates a perfectly legible photograph of the writing may be taken, although there may be no marks on the charred remains that are visible to the eye.  This is the only known method in many cases.  I have here some burned fragments of paper which I gathered up after the first attempt to fire your store, Mr. Stacey.”

Stacey coughed in acknowledgment.  As for Craig, he did not mince matters in telling what he had found.

“Some were notes given in favour of Rebecca Wend and signed by Joseph Stacey,” he said quietly.  “They represent a large sum of money in the aggregate.  Others were memoranda of Miss Wend’s, and still others were autograph letters to Miss Wend of a very incriminating nature in connection with the fires by another person.”

Here he laid the “A.  Spark” letters on the desk before him.  “Now,” he added “some one, in a spirit of bravado, sent these notes to the fire marshal at various times.  Curiously enough, I find that the handwriting of the first one bears a peculiar resemblance to that of Miss Wend, while the second and third, though disguised also, greatly suggest the handwriting of Miss Wend’s correspondent.”

No one moved.  But I sat aghast.  She had been a part of the conspiracy, after all, not a pawn.  Had they played fair?

“Taking up next the remarkable succession of fires,” resumed Kennedy, “this case presents some unique features.  In short, it is a clear case of what is known as a ‘firebug trust.’  Now just what is a firebug trust?  Well, it is, as near as I can make out, a combination of dishonest merchants and insurance adjusters engaged in the business of deliberately setting fires for profit.  These arson trusts are not the ordinary kind of firebugs whom the firemen plentifully damn in the fixed belief that one-fourth of all fires are kindled by incendiaries.  Such ‘trusts’ exist all over the country.  They have operated in Chicago, where they are said to have made seven hundred and fifty thousand dollars in one year.  Another group is said to have its headquarters in Kansas City.  Others have worked in St. Louis, Pittsburgh, Cleveland, and Buffalo.  The fire marshals of Illinois, Kentucky, Tennessee, and Ohio have investigated their work.  But until recently New York has been singularly free from the organised work of this sort.  Of course we have plenty of firebugs and pyromaniacs in a small way, but the big conspiracy has never come to my personal attention before.