The sale of Messrs. Boulton and Fothergill's Manufactory, at Messrs. Christie and Ansell's on April 11-13, 1771, included a dozen vases described as being in 'the antique taste radix amethysti [bluejohn] and or moulu, lined with silver and perferated for essence, supported by four sphinxes upon an ornamented base of ebony'. A pair of bluejohn vases of this model was supplied to George III, in 1771, by Boulton and are in the Royal Collection, Windsor Castle (N. Goodison, Ormolu: The Work of Matthew Boulton, London, 1974, p. 163 and pl. 94). The present lot belongs to a group of perfume-burners which are related to the sphinx vases in form, although they are without the sphinx supports and the lower plinth. They have white marble bodies, with spreading pierced foliate covers, some bear the same lion-mask as the sphinx vases, and some like the above lot have a maiden-mask. They may relate to those in the Boulton and Fothergill sale of 20 May 1778, lots 6, 12, 24, 34 and 35, as 'One pair of statuary marble vases on pedestals, mounted in or moulu and perforated for essences'. Several variations on this model have been sold at auction in recent years. A pair belonging to Lord Wharton, was sold Christie's, London, twice, 19 March, 1970, lot 21 and again anonymously, 6 July 1972, lot 5, when the vases were attributed to Matthew Boulton. Another pair was sold by Mrs. Raymond Gibbs, Christie's, London, 12 March 1981, lot 2. A further almost identical pair was sold anonymously, Christie's, London, 8 July 1999, lot 11 and again from Le Pavillon Chougny, Christie's, London, 9-10 December 2004, lot 379.