GEMS. 
thofe of the Romans fometimes the name of the ai 
fometimes that the owner. his. cuftom, of ad 
the name of the ofleffor, has ferved in more modern 
ion we 
ei has in vain en- 
Not feldom hen names of modern en- 
gravers are written in Greek charaéters, {uch as ©. T. >. fig- 
nifying acBie re Ligdere, or Flavio Sirleti ; TIXLHP, Pich- 
ler, &c. ofe amateurs only, that ar 
ignifies a viper, called hydros sh ae 
erman wor 
S. ome meafure, determine the 
Lower Empire than in any other period; will, with fome 
ee ely that period to be the date of the work 
ion. engravers, undoubtedly very well known 
a a time re ey flourifhed, have put nothing but the 
initials of their names, w hich neceffarily mu 
an arbitrary manner; and this difficul 
name fignifies at the fame time the objet reprefented, and 
therefore leaves us doubtful whether we are to ap ly it 
artifl. Thus the letters HERM, 
The modern dageawes ia have 
mott fuccefsful in copying the names of ancient artifts, are 
Flavian Sirleti, Natter, and a 
fent day; for, according to a compe 
judge in thefe matters, the celebrated Natter, (the refults 
of whofe refearches are a in a treatife entitled « De 
la Méthode A en Pierres fines, comparée 
avec la Méthode Moderne),”” their S$ were not on 
analogous to thofe of modern artifts, but they ufed them 
exatly under the fame circumftanc our 1 
tention to follow the juft-mentioned i ingenious artift in the 
analyfis he has given of a number of antique engravings, 
but we fhall copy one of the mee i it a in the above 
work, together with an outline drawing of the fame head, 
which exemplifies the mode of ie acs employed by the 
engraver of itones. 'Thefe figures, together with thofe repre- 
fenting the lathe and tools ufed by the gem engraver, will 
fuperfede a more detailed a a than the one which 
we are enabled to give in this pla 
e firft geen of the caer is to give 
that is to be employed a form ial ble to the fubjeé 
intends to eri on - This se baad perform 
H draws the out- 
to the ftone 
é he 
ns. 
Fig. 1. (Plate XVII I. Mifcellany) —_ the whole of 
the lathe ; it confifts, as the figure fhews, of a tabl-, on which 
is fixed the mill, ora fal horizontal cylinder of ft 
_— extremities the tool is inferted, and which is turned by 
ans of a vertical wheel below, communicating with the hori- 
al cylinder by means of a cord, and fet in motion by the 
foot of the. artift. Somnetincs the whole of the mill on tha t. 
ap; 
he tools ae ae a ae fixed to aes eny of 
the mill, are, 
Fig. 2.a Hollow cylinder made ufe of to deferibe circles. 
with facility, and alfo for perforating 
Fig. 3 the knobbed tool, called douterollle by 
French ; ; ‘tj is employed in various kinds of work; for ex 
tremities, nts Cc. 
ig. 4.atool, the upper part of which is in the form of a 
ot dill soundea at the edge: it is ufed for various pur- 
Poe g. afimilar tool, but with difks not rounded at the 
the edge. 
Fig. ie the. fame, but with the edge of the {mall > 
pened for the pu hee of cutting into the ftone; it is 
called in n French feie (fav 
The fize of thefe ek varies frow. the bignefs of a large 
pea, to the t of a point fcarcely vifible to the naked e 
It is ane that thefe tools may be varied in ee form, 
according to the fancy of the engraver; but thofe juit 
— a wae generally made ule of. 
e toalis fixed in the manner above defcribed, and 
reprefented in the figure, the artift applies to its point 
diamond-powder, mixed up wit ith olive oil; he turns 
the | Lae ana begins his work, by bringing the {tone faf- 
tened toa piece of wood, into contact with the tool which 
turns round its axis with confider mei velocity. 
ig. 7. reprefents a ftone o nvex fie » with a 
tool applied to it; it thews the sie ntage of w a ing on. 
ftones of that form; for the {pace oa the on and 
the tool being more pee hare in a convex than in a plane 
ftone, the tool penetrates farther on the former than it would 
on the latter. This may be feen y Bg. 8, w vs lead fame 
tool touches bere nearer the bo ie the 
eapelee alle to the ee prducee 
what the oe all fotto quadro; engravings made in this 
manner cannot give a good impreffion. 
There are fome figures which are with difficulty executed 
on ftone, although they appear eafy ; and others that ae 
a eh although they are far from being fo. , for 
inftan » figs. 10, 11, 12, reprefent different angles, “which 
it is no ot matter to eee with nicety.; we generally 
obferve imperfe@ execution in fuch angles, where the rouad 
tool cannot . made to touch. 
figs 13. c<agon, which may be ga bakeg without 
difficulty, fie all.its points pabieg “ous ng by two and twoy 
nothin ng is requi red but to trace three lines, croffin each” 
other in a common pas peer difficulty there is with 
regard to the letters, which cannot be executed in the manner 
of thofe that are feen on medals (fee fig. 17.) ; the tool 
will always leave na imperfeétion in the angles of the ex- 
tremities, as appears in fig. 14 and 15. e beft engravers 
of an tiquity have ‘preferred to make ufe of ie bouterolle 
Se 
The head of Jupiter Serapis, oo fa 2 17, and. 
18, is given by Natter, as an example of the mode of pro- - 
ae in order to produce a work of that defcription. 
above, fu a ge 18. 
is flat or canes provided i it be of fu fficient thicknefs to bear 
fixed : a handle, as above defcribed, 
but left this operation fhould produce a round figure inftead 
of an oval, the ftone is to be gr adually moved i in the dire€tion 
of 
