irst been used
systematically by Elisha Kirkall in 1722-24, and by Arthur Pond in his
chiaroscuros, made in 1732-36 in conjunction with George Knapton, after
drawings by old masters. Jackson admired Pond's work even though it
combined etched outlines with two tone blocks printed from wood.[30]
Pond's embossing was delicate and applied sparely only in certain forms,
such as ruined columns, but Jackson's sunken areas were heavier and
franker, consciously intended to give an all-over effect. Since the
paper could not be pressed out without weakening the embossing, it often
took on the scarred and buckled look that characterizes the Venetian
chiaroscuros.

[Footnote 30: _Enquiry_, p. 35. The Japanese began to use
embossing about 1730. See Reichel, 1926, p. 48.]

The set had occupied him for 4-1/2 years, during which he had planned,
cut, and proofed 94 blocks.

No sooner was that ended, and a little Breathing required after that
immense Fatigue, in the Year 1744 he attempted to print in Colours,
and published six Landskips in Imitation of Painting in Acquarello.

[Illustration:
Title page for _Gajo Suetonio tranquillo, le vite de'dodici
Cesari_, Piacentini, Venice, 1738.]

This new set, dedicated to Robert d'Arcy, British Ambassador to the
Republic of Venice, was based on gouache paintings by Marco Ricci,
probably done on goatskin or leather in his usual manner. For Jackson to
make these color prints was a logical step, since his work had tended
toward the full chromatic range even in the chiaroscuros, which
"adumbrated" color. His new prints were all color-- clear, sensitive,
and tonally just. It is not surprising that he seized upon Ricci's
opaque watercolors. The paintings of the Venetian masters had darkened
in ill-lit churches, the shadows had become murky, there were too many
figures. But the Ricci paintings were small and clearly patterned, the
color sparkled.

The original gouaches have not been located, but from other examples in
the same manner, in Buckingham Palace and in the Uffizi, it is plain
that Jackson took certain liberties. Ricci's rather sharp colors were
considerably modified and mellowed when they weren't changed entirely:
witness the two sets in different harmonies in the British Museum. Peter
A. Wick (1955) believes it most likely that Jackson did not copy
specific paintings, and suggests that details from Ricci's etchings and
gouaches were combined and freely amended