A half-length portrait by the German painter, Karl Anton Hickel, is in the National Portrait Gallery, where there is also a terra-cotta bust by Nollekens.
Other panel portraits of the period are three small ones of members of the Tucher family at Weimar and Cassel, and the striking, restlessly elaborated half-length of Oswald Krell at Munich.
The canvas, 36 X 28 in., admitted of less than a half-length portrait but was sufficiently long to include a hand, and this is known as the kit-cat size.
The last, which may have been done since he settled in France, is the darkened and partly repainted, but still powerful and haunting half-length figure in the Louvre, with the smile of inward ravishment and the prophetic finger beckoning skyward like that of St Anne in the Academy cartoon.
The proportions of cone pulleys for open or crossed belts may be determined by considering the expression for the half length (1) of a belt wrapping round pulleys of radius r 1 and r 2 respectively, and with centres distant c apart.