The professor shook his head pityingly. "Oh, no, sir," he said. "None but bunglers ever undertake a job like this. Here, sir, are two forged signatures. If one genuine signature, standing alone, has one chance in a million of being exactly like any previous signature of the writer, two standing together have not one chance in ten millions of being exact fac-similes of two others brought together by chance.
"How were these fac-similes produced?" inquired Mr. Balfour.
"They could only have been produced by tracing first with a pencil, directly over the signature to be counterfeited."
"Well, this seems very reasonable, but have you any further tests?"
"Under this magnifying glass," said the professor, pushing along his examination at the same time, "I see a marked difference between the signatures on the two papers, which is not apparent to the naked eye. The letters of the genuine autograph have smooth, unhesitating lines; those of the counterfeits present certain minute irregularities that are inseparable from pains-taking and slow execution. Unless the Court and the jury are accustomed to the use of a glass, and to examinations of this particular character, they will hardly be able to see just what I describe, but I have an experiment which will convince them that I am right."
"Can you perform this experiment here, and now?"
"I can, sir, provided the Court will permit me to establish the necessary conditions. I must darken the room, and as I notice that the windows are all furnished with shutters, the matter may be very quickly and easily accomplished."
"Will you describe the nature of your experiment?"
"Well, sir, during the recess of the Court, I have had photographed upon glass all the signatures. These, with the aid of a solar microscope, I can project upon the wall behind the jury, immensely enlarged, so that the peculiarities I have described may be detected by every eye in the house, with others, probably, if the sun remains bright and strong, that I have not alluded to."
"The experiment will be permitted," said the judge, "and the officers and the janitor will give the Professor all the assistance he needs."