A deeply interesting historical instance of this tendency of handwriting to vary with the mood of the writer is to be seen in the signatures of Napoleon at various periods of his career. Several of these written on occasions calling forth widely differing emotions are here reproduced, and it is not difficult to discern in some of them the effect of emotional influence. Very striking, for instance, is the difference between the orderly signature written after the victory at Austerlitz and the blotted scrawl dashed off after the defeat at Leipzig. Nor will it escape notice that nearly all the signatures written at moments of depression or failure have a downward slant, whereas that of the victor of Austerlitz runs upwards. A great contrast, too, is shown between the general features of the first three signatures penned in moments of triumph or success, with that written on the retreat from Russia and the still less assertive signature of the prisoner of St. Helena.
Instances of the effects of passing emotions upon writing might be multiplied indefinitely, but what has been said above is sufficient to show that this factor is of importance in drawing any conclusions as to the identity of an individual from his handwriting.
 | 1804. After being crowned Emperor. | |
 | 1805, Dec. 2. Signature on proclamation after the victory at Austerlitz. | |
 | 1806. After the campaign of 1806. | |
 | 1812, Sept. 21. After entrance into burning Moscow. | |
 | 1812, Oct. On the retreat from Russia. | |
 | 1813, Oct. 23. Signature to a document signed at Erfurt. After the defeat at Leipzig. | |
 | 1814, April 4. Fontainebleau, prior to abdication. | |
 | At St. Helena. |
SIGNATURES OF NAPOLEON AT DIFFERENT PERIODS OF HIS CAREER
If passing emotions can have so great an influence upon handwriting, how much greater must be the effect when the centre or centres in the brain that control the writing mechanism are affected or destroyed by disease!
Among the disturbances of handwriting due to defective control of the muscles we may include the so-called tremor-writing, which is common in old age, and the writing of people suffering from writers’ cramp, an example of which is shown in the figure.
Writers’ Cramp
Other forms of defective writing may be the result of a paralytic stroke affecting the writing centre of the brain, which causes the patient either to form only parts of letters or endlessly to repeat the same letter under the impression that sentences are being formed, while in extreme cases there may be merely a succession of meaningless strokes in place of written characters.