His power of work was marvellous. He painted over six hundred and twenty pictures, executed three hundred and sixty-five etchings, besides two hundred and thirty-seven variations of these, with hundreds of drawings and sketches scattered over Europe. Among the best known etchings are "Rembrandt's Portrait with the Sword," "Lazarus rising from the Dead," the "Hundred-Florin Plate," "Annunciation," "Ecce Homo," "The Good Samaritan," "The Great Descent from the Cross," the landscape with the mill, and that with the three trees. That he was a man of great depth of feeling is shown by his love of his mother, his worship of Saskia, and his tenderness to his brothers and sisters after they had lost their fortunes. He was also passionately fond of nature and of animals. Sweetser tells this incident: "One day he was making a portrait group of a notable family, when he was informed that his favorite monkey had died. The grieving artist caused the body to be brought to the studio, and made its portrait on the same canvas on which he was engaged. The family, aforesaid, was naturally incensed at such an interpolation, and demanded that it should be effaced; but Rembrandt preferred to keep the whole work himself, and let his patrons seek a more accommodating artist." Taine pays Rembrandt this glowing tribute in his "Art in the Netherlands:" "Rembrandt, constantly collecting his materials, living in solitude and borne along by the growth of an extraordinary faculty, lived, like our Balzac, a magician and a visionary in a world fashioned by his own hand, and of which he alone possessed the key. Superior to all painters in the native delicacy and keenness of his optical perceptions, he comprehended this truth and adhered to it in all its consequence,--that, to the eye, the essence of a visible object consists of the spot (_tache_), that the simplest color is infinitely complex, that every visual sensation is the product of its elements coupled with its surroundings, that each object on the field of sight is but a single spot modified by others, and that in this wise the principal feature of a picture is the ever-present, tremulous, colored atmosphere into which figures are plunged like fishes in the sea.... "Free of all trammels and guided by the keen sensibility of his organs, he has succeeded in portraying in man not merely the general structure and the abstract type which answers for classic art, but again that which is peculiar and profound in the individual, the infinite and indefinable complications of the moral being, the whole of that changeable imprint which concentrates instantaneously on a face the entire history of a soul, and which Shakespeare alone saw with an equally prodigious lucidity.