Even a simple banderole or scarf suffices to indicate movement in the air if well arranged. Usually a flying cherub holds an end of the banderole, and Ferri shows a wingless putto even, flying with no other assistance.[a] Boucher creates an illusion by the bold device of connecting two cupids with a narrow scarf blown out into a semicircle[b]; and in another instance very narrow tape streamers suffice.[c] [a] David plans a Temple. [b] Birth of Venus. [c] Altdorfer's Nativity at Berlin. The use of thick smoke for suspension purposes is nearly always successful, because volumes of smoke in nature necessarily tend to move upwards; but obviously this scheme can only be arranged when an altar is possible. The plan is not uncommon in pictures relating to Cain and Abel, and the Translation of Enoch. In one of the latter subject, Hoet makes part of the smoke from an altar envelop the surrounding ground so as to widen the volume, while Schnorr achieves the same end by curling round the smoke as it ascends into the form of a large saucer upon which the Deity sits,[a] a method slightly varied by Amiconi.[b] [a] God's Promise to Abraham. [b] God Appearing to Moses. Where a number of figures are connected together in a circular form in the air, the double illusion of suspension and motion follows naturally, provided their attitudes indicate a circular movement. An excellent example of this is shown in a picture by Botticelli, where Angels dance in the air over the hut of the Nativity.[a] The finest work of the kind in existence is probably Schwind's Pleiads, in which the stars are represented by a circle of beautiful nude women.[b] Extraordinary activity is suggested by the perfect arrangement of the limbs and light flowing drapery used. Bouguereau has a work of a similar kind, The Lost Pleiad, but here the dancers are upright, and the circle is only accessory to the title figure.[c] Watteau is fairly successful in giving an illusion of suspension to cupids even with a half circle, though the invention is somewhat formal.[d] [a] National Gallery, London. [b] Denner Collection. See Plate 25. [c] Brooklyn Museum, New York. [d] The Berlin example of the Embarkation for Cythera.