“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.”

Gradually, as the shutters were closed, the room grew dark, and the faces of Judge, Jury and the anxious-looking parties within the bar grew weird and wan among the shadows.  A strange silence and awe descended upon the crowd.  The great sun in heaven was summoned as a witness, and the sun would not lie.  A voice was to speak to them from a hundred millions of miles away—­a hundred millions of miles near the realm toward which men looked when they dreamed of the Great White Throne.

They felt as a man might feel, were he conscious, in the darkness of the tomb, when waiting for the trump of the resurrection and the breaking of the everlasting day.  Men heard their own hearts beat, like the tramp of trooping hosts; yet there was one man who was glad of the darkness.  To him the judgment day had come; and the closing shutters were the rocks that covered him.  He could see and not be seen.  He could behold his own shame and not be conscious that five hundred eyes were upon him.

All attention was turned to the single pair of shutters not entirely closed.  Outside of these, the professor had established his heliostat, and then gradually, by the aid of drapery, he narrowed down the entrance of light to a little aperture where a single silver bar entered and pierced the darkness like a spear.  Then this was closed by the insertion of his microscope, and, leaving his apparatus in the hands of an assistant, he felt his way back to his old position.