For several years Mr. D. N. Carvalho, the New York photographer, has made a specialty of the delicate use of photography which is brought into play more and more in connection with criminal cases in which disputed handwriting, forgeries, counterfeit money, etc., are features. The results now achieved are the outcome of years of experiment, and the photographic expert becomes in the end an expert in handwriting. Mr. Carvalho's gallery of records is an interesting illustration of what perseverance and ingenuity, aided by photography, can do toward solving apparently hopeless mysteries. To a reporter, who visited his studio, he said:

"We can do a great many things to bring the truth to light by the aid of photography. There is scarcely a case nowadays in which it is not brought into play if disputed handwriting is concerned. Of course the most famous case of late years was the Morey letter case. There is a photograph of the Morey letter up there in a corner. It yet remains a mystery, but we are certain that Garfield did not write it. I first found by photography that the envelope had been tampered with by the following process: Cutting the envelope open, so as to get a single thickness of paper, I put it between two sheets of plate glass, and placed it where the sun passed through it, the camera being placed on the shady side. Although no half-erased writing could be detected on the envelope with the naked eye or a glass, the difference in the thickness of the paper where erasures had been made showed plainly, as the light came through more clearly, and the erased words, which gave rise to so much discussion, were discovered.

"Below the Morey letter is a photograph of the signature of Alonzo C. Yates. Yates, you may remember, was a rich Philadelphia clothier, who, late in life, married a cook in the Astor House, and died, leaving a million or so to the wife. The daughters by a first wife disputed the signature to the will. I was employed by John D. Townsend to show the genuineness of the signature. We got thirty or forty genuine signatures of Yates admitted by both sides, and showed that a man never writes his name the same way twice. Then I took the signature of the will and another admitted by both sides, and enlarged them until each was 9 feet 4 inches long. The peculiarities of the writing became so apparent when shown upon that enormous scale—the signatures were so evidently by the same person—that the contestants gave up the case.

"There is a portrait of Theophilus Youngs. He married a clairvoyant many years ago in Boston and disappeared. His widow pretended to recognize his body in one that was found in the bay soon after, and he was given up as dead. Some years after his father died, and the widow put in a claim for a share of the property. The contestants, by whom I was employed, contended that Youngs was yet alive, and eventually produced him in court. The alleged widow refused to recognize him, and I was called upon to prove he was the man. The widow produced a photograph which she said was one of the pictures of Youngs, her husband. A good many years had passed, and although the likeness was a strong one, there was enough difference in the appearance of Youngs and the photograph to make a jury hesitate. I put Youngs in the same position in which he was taken in the picture, the genuineness of which was admitted, and made a photograph of the same size. Then the likeness became more apparent, and exact measurements showed the two faces to measure the same in all respects. For instance, the distance between the mouth and the eye, which is seldom the same in two persons, was exactly equal. Then one picture was made transparent and superimposed over the other, and the two faces matched perfectly. The jury decided that the claimant was not an impostor.

"In the case of Hall, the head clerk of the Newark Treasurer's office, everything depended upon showing that he changed a figure 5 into a figure 3. He ran away to Canada, and was brought back upon a charge of forgery. His counsel claimed that the figure had not been changed, and that if the mark of an eraser was found, and that the figure 5 had been changed, it was caused by the accidental slip of an ink eraser used in the margin. I made photographs of the page, and by means of a stereopticon threw a picture of that particular figure upon a screen 10 feet high. Upon that scale several interesting things came out. It was seen very plainly that the figure had been altered from a 5 to a 3, but the erasure had been made with a different material from the erasure in the margin. We tried a rubber ink eraser, and the result was the same as seen in the margin. Then we tried a steel penknife, and the result enlarged a thousand times was the same as seen over the figure 3. This disposed of the 'accident' theory, and Hall was convicted.

"I was employed in the Cadet Whittaker case, and worked for weeks at the famous letter of warning—a few words scribbled on a piece of paper, which Whittaker was suspected of writing. All the cadets were called upon to give specimens of their handwriting, and the writing of No. 27 was declared by the experts to be that of the note of warning. I believed that it was not, and, taking the specimen of No. 27's writing upon which he was suspected, I duplicated the note of warning, cutting the same letters out of 27's specimen, and placing them together as nearly as possible in the order of the famous note. It was a work of tremendous labor, but when done it showed the innocence of No. 27. It was suspected that the scrap of paper upon which the note of warning was written was torn from a letter sheet which Whittaker sent to his mother, but that theory was disposed of upon enlarging the two edges to the size at which a fine cambric needle looks like a crowbar. Then it was seen that the two edges had never been together. The verdict in the Whittaker case was finally reversed upon the ground that the court had come to a decision from the examination of lithographs of the note of warning, which I proved by comparison with a photograph were incorrect. Whittaker, by the way, is teaching school now in the northern part of this State. He made speeches for Cleveland in his neighborhood during the election campaign last autumn."