typical. +Muenz+, op. cit., vol. 2, p. 47, gives a listing of the
surviving plates, but mistakenly presumes the Humber plates to be in the
Bibliotheque Nationale, Paris. As a matter of interest, the plate of the
print, _The Gold-Weigher_ (Hind 167), said by Muenz to be in the
Rosenwald collection, Philadelphia, is not and never has been in that
collection. It is completely unknown to Mr. Lessing J. Rosenwald and his
curator. Its present whereabouts is unknown to the author.

[17] _The Whole Art of Drawing, Painting, Limning, and Etching.
Collected out of the Choicest Italian and German Authors.... Originally
invented and written by the famous Italian Painter Odoardo Fialetti,
Painter of Boloign. Published for the Benefit of all ingenuous Gentlemen
and Artists by Alexander Brown Practitioner. London, Printed for Peter
Stint at the Signe of the White Horse in Giltspurre Street, and Simon
Miller at the Starre in St. Paul's Churchyard, MDCLX._ Page 33. London,
1660. Quoted by +Muenz+, op. cit., vol. 2, p. 208, who first discovered
the reference. Since Fialetti died in 1638, the reference to Rembrandt's
ground is likely to be by Brown or an anonymous contemporary editor.

[18] +Abraham Bosse+, _Traicte des manieres de graver en taille
douce_ ..., Paris, 1645, p. 41. Bosse's soft-ground formula, for
comparison's sake, is three parts wax, two parts mastic, and one part
asphaltum, which is very close to the cited Rembrandt ground.

[19] Numerous similar grounds are given in +E. S. Lumsden+,
_The Art of Etching_ (London: Seeley Service and Co., 1924); reprint
(New York: Dover Publications, Inc., 1962), pp. 35-38.

[20] Loc. cit. (footnote 17).

[21] Some etchers, however, prefer this effect. Cf. +Lumsden+,
op. cit., p. 42.

[22] +Muenz+, op. cit., vol. 2, p. 13, quotes this letter
without giving the source. Evidently this is the first written reference
to white ground.

[23] Op. cit., pp. 46-48. Knowledge of the process seems to
have disappeared completely during the 18th and 19th centuries. Hubert
Herkomer, writing in 1892, believed that he had invented the white
ground for the first time (_Etching and Mezzotint Engraving_, London,
1892, pp. 4 and 25).

[24] The etching is Hind 42. The drawing (Benesch 21, Hofstede
de Groot 893) is in the British Museum. The black chalk has been
confirmed (see footnote 25). It is also clear that the backing is not
graphite, which would, of course, show up on a black ground as well as