statements that he was quite bewildered, and he left the Tribunal with
his photographic reputation sadly shattered.

Another witness was summoned, the Court being determined to get at the
bottom of the problem which had been raised. They certainly recognised
the significance of my contention. This time it was a military officer.
He was examined by the Court, and then I was given the liberty to
cross-examine. My very first question was adequate to satisfy myself
that he knew even less about the subject than the previous witness. But
he was nervously anxious not to betray his ignorance. He had been called
in as an expert and fervently desired to maintain this reputation. He
did so by acquiescing in every statement which I put to him concerning
the action of light upon nitrate of silver.

"Now," I asked emphatically, when I had completely caught him, "under
these circumstances, and according to what you have been explaining to
the court, the second half of this film which is transparent has never
been exposed?"

"It has not."

His negative was so emphatic as to convince the Court. I had scored the
crucial point and felt, now my supreme difficulty had been subjugated so
conclusively, that all was plain sailing. It was only too evident that
everything had turned upon that short length of unexposed film, and I
felt devoutly thankful to Providence that the light had not accidentally
penetrated to the sensitised surface. Had the unexposed section been
black my fate would have been irrevocably sealed.

Now I was asked to present my defence.