Chiefest among the essential qualities is to be named his astonishing strength of nerve.  No danger could agitate him, however imminent or sudden.  No power could deprive him of his imperturbable coolness and courage.  Perils seemed to render his mind more clear and his self-reliance more firm. (And yet I have heard him say, that there was among the band of criminals before mentioned one woman of greater strength of mind and nervous power than any person he had ever seen, whom alone of all created beings, whether man or devil, he dreaded to encounter.) Had not Mr. Sidney been thus potently armed, he must, without doubt or question, have become almost a monomaniac; for, secondly, he was for years enraged almost to madness that his entire estate had been swept from his grasp, as he believed, by the torch of the incendiary; and he was to the last degree exasperated, and with a just indignation, that the merchant-princes who he supposed had occasioned his impoverishment yet walked abroad with the confidence of the community, and were still trusted by many a good man as the very salt of the city.  Nevertheless, Mr. Sidney, solitary and alone, had arraigned them before a criminal tribunal.  He was therefore driven to his own resources, and there was no place in his nature, or in the nature of things, for the first retrograde step.  All his vast energies were thenceforth consecrated to, and concentrated in, the detection of crime.  And from the time that he was refused payment for his loss, so far as my observation extended, he seemed to have been governed by no other purpose in life than the extermination of that great gang of robbers which he subsequently discovered.  Add to these incentives and capacities his extraordinary perceptive faculties and power of analytical observation, together with his wonderful patience, and it must be granted that he was qualified to discover in any incident connected with his pursuits more of its component parts than all other beholders, and had greater opportunities than almost any other man by which to be informed how it is that “the heart of a man changeth his countenance.”

If I remember rightly, it was some two years after our acquaintance commenced that I became aware of Mr. Sidney’s proficiency as a physiognomist, and it was then communicated, not so much by his choice as by a necessity, for the accomplishment of one of his purposes.

The object of Mr. Sidney’s visit to the city of P——­, at that time, was nothing less difficult than the discovery and identification of an individual of whom no other knowledge or description had been obtained than what could be extracted from the inspection, in another city, of a single specimen of his handwriting in the superscription of a letter.  So much from so little.  Within three days thereafter, with no other instrumentalities than what were suggested by Mr. Sidney’s expertness in deciphering character in handwriting and his proficiency as a physiognomist, the result was reached and the object happily attained.  In the prosecution of the enterprise, it was important, if not essential, that I should believe that the data were sufficient by which to arrive at a correct conclusion, and that I should confide in Mr. Sidney’s skill in order that there might be hearty cooeperation.