not loud, but so distinct that it carried to the furthest benches.  No syllable was slurred, no point hurried over.  All this made for the lucid and comprehensible; well-chosen language and fine utterance shaped a perfect vehicle of thought.  But it was the lucidity of the thought itself, thus expressed, that gave his lectures their quality.  A clever and accomplished lady once, in intimate conversation, asked Mrs. Huxley what the reason could be that every one praised her husband so highly as a lecturer.  “I can’t understand it.  He just lets the subject explain itself, and that’s all.”  Profound, if unintended, compliment.  It was his power of seeing things clearly, stripped of their non-essentials, that enabled him to make others see them clearly also.  Nor did he forget the saying of that prince of popular expositors, Faraday, who, when asked, “How much may a popular lecturer suppose his audience knows?” replied emphatically, “Nothing.”  This same faculty, no doubt, was that which enabled him to write such admirable elementary text-books—­a task which he regarded as one of the most difficult possible.

A notable description of his public lecturing in the seventies and early eighties is given by G. W. Smalley, correspondent of the New York Tribune, in his “London Letters":—­

[Illustration:  From a Photograph by Maull and Polyblank, 1857; To face p. 44]

I used always to admire the simple and businesslike way in which Huxley made his entry on great occasions.  He hated anything like display, and would have none of it.  At the Royal Institution, more than almost anywhere else, the lecturer, on whom the concentric circles of spectators in their steep amphitheatre look down, focuses the gaze.  Huxley never seemed aware that anybody was looking at him.  From self-consciousness he was, here as elsewhere, singularly free, as from self-assertion.  He walked in through the door on the left as if he were entering his own laboratory.  In these days he bore scarcely a mark of age.  He was in the full vigour of manhood, and looked the man he was....  With a firm step and easy bearing he took his place, apparently without a thought of the people who were cheering him.  To him it was an anniversary.  He looked, and he probably was, the master.  Surrounded as he was by the celebrities of science and the ornaments of London drawing-rooms, there was none who had quite the same kind of intellectual ascendancy which belonged to him.  The square forehead, the square jaw, the tense lines of the mouth, the deep, flashing dark eyes, the impression of something more than strength he gave you, an impression of sincerity, of solid force, of immovability, yet with the gentleness arising from the serene consciousness of his strength—­all this belonged to Huxley, and to him alone.  The first glance magnetized his audience.  The eyes were those of one accustomed to command, of one having authority, and not fearing on occasion