to use it.  The hair swept carelessly away from the broad forehead and grew rather long behind, yet the length did not suggest, as it often does, effeminacy.  He was masculine in everything—­look, gesture, speech.  Sparing of gesture, sparing of emphasis, careless of mere rhetorical or oratorical art, he had, nevertheless, the secret of the highest art of all, whether in oratory or whatever else—­he had simplicity.  The force was in the thought and the diction, and he needed no other.  The voice was rather deep, low, but quite audible; at times sonorous, and always full....  His manner here, in the presence of this select and rather limited audience—­for the theatre of the Royal Institution holds, I think, less than a thousand people—­was exactly the same as before a great company whom he addressed at Liverpool, as President of the British Association for the Advancement of Science.  I remember going late to that and having to sit far back, yet hearing every word easily; and there, too, the feeling was the same—­that he had mastered his audience, taken possession of them, and held them to the end in an unrelaxing grip, as a great actor at his best does.  There was nothing of the actor about him, except that he knew how to stand still; but masterful he ever was.

Equally perfect of their kind were his class lectures, which made a deep and lasting impression on his students.  In the words of Jeffery Parker, afterwards his assistant:—­

His lectures were like his writings, luminously clear, without the faintest disposition to descend to the level of his audience; eloquent, but with no trace of the empty rhetoric which so often does duty for that quality; full of a high seriousness, but with no suspicion of pedantry; lightened by an occasional epigram or flashes of caustic humour, but with none of the small jocularity in which it is such a temptation to a lecturer to indulge.  As one listened to him one felt that comparative anatomy was worthy of the devotion of a life, and that to solve a morphological problem was as fine a thing as to win a battle.  He was an admirable draughtsman, and his blackboard illustrations were always a great feature of his lectures, especially when, to show the relation of two animal types, he would, by a few rapid strokes and smudges, evolve the one into the other before our eyes.  He seemed to have a real affection for some of the specimens illustrating his lectures, and would handle them in a peculiarly loving manner.  When he was lecturing on man, for instance, he would sometimes throw his arm over the shoulder of the skeleton beside him and take its hand, as if its silent companionship were an inspiration.  To me, his lectures before his small class at Jermyn Street or South Kensington were almost more impressive than the discourses at the Royal Institution, where, for an hour and a-half, he poured forth a stream of dignified, earnest, sincere words in perfect literary form, and without the assistance of a