Undoubtedly the nearest in merit to Cosway was Andrew Plimer, and some of his works are fascinating in their beauty, but in charm they are never equal to those of Cosway, and the peculiar mannerisms of the artist prevent them from being altogether satisfactory. Plimer had very little power of composition, and he invariably over-accentuated the eyes of his sitters, and constantly repeated a favourite pose either of head or figure, while the extraordinary wiry manner in which he delineated the hair marks out his work at once. Quite as noticeable is his affection for the appearance of his own daughters, and the very shape of their necks and brilliance of their eyes can be seen repeated over and over again in his portraits of other sitters. Less than most of his contemporaries was he able to break away from a strong personal characteristic; and eventually it became a species of obsession with him, so that his female portraits strikingly resemble one another.
John Smart was a painter of a different type, serious, solid, painstaking. His facial modelling is extraordinary in its accuracy, and his works, like those of Engleheart, appear to have been preferred by the more serious persons in society, whereas those of Cosway and Plimer were particularly appreciated by the gay and frivolous ladies of the Court circle, whose sun and centre was the Prince Regent.
There are miniatures by Cosway which are of pre-eminent beauty, so lightly and with such exquisite skill are they floated upon the ivory. The quality of the material had, of course, an intimate connection with the art of the painter. The seventeenth-century artists knew nothing of the brilliant surface of ivory, although it is possible that one at least of them had an inkling that a more luminous material than vellum, cardboard, or chicken-skin, could be found. There are two miniatures in existence, one of which is in the possession of the author of these pages, the work of Cooper, which are not painted on any of the materials usually adopted by him. This latter is painted on what was at first thought to be a piece of ivory, but microscopic investigation has revealed the fact that it is polished mutton-bone, and the painter has so altered his technique to adapt it to this curious experiment, that for the first moment one would hardly believe the miniature to be by Cooper at all. Its pedigree is, however, unassailable, and a closer investigation reveals many of the master's characteristics, but it is painted with a very fine brush, quite different to the usual broad, full sweep of his work, and it stands out as an interesting experiment on the part of the great painter, who was searching for some material more suitable for a particular style of work. Ivory was not employed until the time of William III., and it seems probable that one of the Lens family was the first to make use of it; but, once adopted, its use became very general, and in the prolific period of the eighteenth century, almost universal.