pictures claimed to be original by Da Vinci, even in the public galleries of Europe, were executed by his pupils and imitators, several of whom copied and imitated him with great success. Lanzi says that Lorenzo di Credi approached him so closely, that one of his copies of Lionardo could hardly be distinguished from the original. For a list of his imitators, see Spooner's Dictionary of Painters, Engravers, Sculptors, and Architects, table of Imitators.
WORKS IN NIELLO.
The art of working in niello, which led Maso Finiguerra,
a sculptor and worker in gold and silver,
to the invention of copper plate engraving, was very
early practiced in Italy. In the 15th century, and
long before, it was the practice to decorate the
church and other plate with designs in niello; and
also caskets, sword and dagger hilts, and various
kinds of ornaments. The designs were hatched with
a steel point in gold or silver, then engraved with
the burin, and run in while hot, with a composition
called niello, an Italian term derived from the Latin
nigellum—a compound of silver, lead, copper, sulphur,
and borax, used by the ancients, and easily
fusible, and of a dark color. The superfluous parts
of the niello were then scraped away, and the surface
polished, when the engraved part appeared with
all the effect of a print. Lanzi says, "this substance
(nigellum) being incorporated with the silver, and
