364 Rev. Mr. Conybeare on Works in Niello, and the [Nov. 
drawing through melted wax. This wick is placed in a burner” 
made of a bit of tinned iron sheet, cut like fig. 3, and the two 
parts a a raised into fig. 4. _ 
This burner is placed in a china cup, about 1:65 inches in 
diameter, and 0’6 in. deep. Fragments of wax are pressed into 
this cup. But great care must be taken that each time the lam 
is lighted, bits of wax are heaped up in contact with the wick, 
so that the flame shall immediately obtain a supply of melted 
wax. This is the great secret on which the burning of wax 
lamps depends. . 
When the wick is consumed, the wax must be pierced with a 
large pin down to the burner, and a fresh bit of waxed cotton 
introduced. 
I employ a wax lamp for the blowpipe. This has, of course, 
a much larger wick, and this wick has a detached end to it, as 
above described. 
Extinguishing Lamps.—The best way of doing this is to 
extinguish the ignited part of the wick by putting sound wax on 
to it, and then blowing the fame out. ‘This preserves the wick 
entire for future lighting again. 
This mode applied to candles is much preferable to the use of 
an extinguisher, or douters, to which there are many objections. 
ArTICLE XI. 
On Works in Niello and the Pirotechnia of Venoceio Biringuccio 
Siennese. By the Rev. J. J. Conybeare. 
(To the Editor of the Annals of Philosophy.) 
DEAR SIR, Bath Easton, Oct. 14, 1822. 
In Mr. Ottley’s interesting and learned History of Engraving, 
vol. i. pp. 262 and 270, two accounts are given of the process 
‘used in the execution of the ornamental work termed Niello : the 
former, very short, and evidently inaccurate, from Vasari; the 
latter from a modern virtuoso (the Count Seratti), whose state- 
ment, although more correct, is unsupported by any reference to 
earlier authorities, not to mention that Seratti himself is (as Mr. 
Ottley with justice remarks) somewhat wanting both in accu- 
racy and in judgment. It is sufficiently known that the Niello 
(independently of the esteem in which it was once held, and the 
real merits and beauty of the works executed in it by Finiguerra 
and others) has been yet more ennobled by having given birth to 
the invaluable art of transferring impressions trom engraved 
plates to paper. The following description, therefore, of the 
‘mode which seems to have been usually adopted for the compo- 
