The copy of a genuine signature may be free-hand or composite, by which is meant that the writing is produced discontinuously or in parts. Comparison of the separate letters of the doubtful specimen of writing with the separate letters of the genuine writing of the supposed imitator or imitated always exhibits less uniformity if imitation has been attempted, the copyist being frequently led into an approach to his ordinary handwriting or into an oversight of some special characteristics of the writing he is simulating. Even minor points do not escape the expert's critical attention. The dotting of the i's, or crossing of the t's, curls, loops, flourishes, intervals between words and letters, connections, characteristics of up and down strokes are all carefully noticed.
A glass of low magnifying power will, as a rule, exhibit erasures, and even bring to view the erased letters. In tracing, the forger frequently fails to cover over the first outlines, which can be plainly distinguished. The places where the pen has been put upon and removed from the paper may sometimes be noticed, which is in itself strong evidence of fraud.
With the aid of a microscope the character of the alterations, certain characteristics due to age, emotion, etc., the kind of pen used and how it was held, the nature of ink, order of writing, with regard to time, whether produced by the right or left hand, standing or sitting, can often be determined. Indentations made by heavy strokes or a sharp pen, as well as those employed as guides for the signature subsequently written, will also be brought into prominence. Forged signatures placed under the microscope have generally a patched appearance, which results from the retracing of lines in certain portions not occurring in genuine writing.
In case of disputed handwriting photography has also been employed to great advantage. Of course the writing in question should, whenever practicable, be compared with the original, photographic copies being looked upon with disfavor and considered by most courts as secondary evidence. Still, photographic enlargements of genuine and disputed signatures are very useful in illustrating expert testimony. Certain characteristics, differences in ink, attempts to remove writing, etc., may be brought to view, which would be entirely overlooked by direct examination. The wonderful power of the camera has recently been illustrated in a very striking manner. A large ocean steamer was photographed, and on receipt of the proof the owners were surprised to see a hand bill posted on the side of the hull. Examination of the ship disclosed no hand bill there, but another photograph exhibited the same result. A searching inspection revealed the presence of the mysterious paper buried beneath four coats of paint, but defying the superficial scrutiny of the human eye.
As a last resort chemical tests may be applied, by which the identity or difference of the inks used may be established, etc. As a means of demonstrating that chemical erasures have been made a certain manipulation and treatment of the paper submitted will almost invariably bring back the original and obliterated writing.
A few words regarding papers and documents, intended for preservation, will not be amiss. Improved processes of manufacture have certainly had no beneficial influence on the durability of the products, and while inks and papers have become greatly reduced in price and apparently improved in quality, it is very doubtful if much of our book learning and many of our written instruments will go down to future generations. Even fifty years will suffice to decompose many an attractive volume at present on the shelves of our libraries, or fade the writing of finely engraved and important documents. The quality of the ink and paper selected is therefore of greatest importance. Typewritten copies particularly are subject to the ravages of time, and ought to be avoided when preservation for years to come is the principal consideration, as for instance in the case of wills, etc., which ought to be made in one's own handwriting whenever practicable.
Briefly, I may state that all the safeguards employed on commercial papers or legal documents, outside of the actual protection afforded, have the beneficial effect or tendency to make forgeries, erasures or alterations more difficult, at the same time warning prospective forgers to keep a respectful distance.
The inks used, the position of the writing, the paper on which it is written, the employment of certain chemical, mechanical and clerical preventatives are all to be thoughtfully considered by those who desire to protect themselves against losses resulting from fraudulent handwriting.
With regard to expert testimony it may be said in conclusion that it is most effective if governed solely by the evidence submitted, and not by information otherwise obtained. The microscopic and photographic examination of papers and documents, as well as their mechanical and chemical treatment, require in all cases the trained eye, the skilled hand and the extensive experience of the expert, in order to fully utilize the available material and to arrive at conclusions which are in entire accord with the facts under consideration, thereby aiding in the just and equitable settlement of weighty questions of profit or loss, affluence or poverty, liberty or imprisonment, life or death.
Another expert in handwriting says that regarding the methods made use of to determine authorship, specialists are naturally reticent. Some of them have admitted, however, the nature of the leading principles' which guide them. The philosophy of the matter rests mainly on the fact that it is very rare for any two persons to write hands similar enough to deceive a careful observer, unless one is imitating the other. "Fists," like faces, have all some special idiosyncrasy, and the imitator has not merely to copy that of some one else but to disguise his own.