36 
From Sandyx and Sinopis, another colour, Syricnm, is 
prepared, which Pliny says is used to adulterate first-class 
minium, and he continues one motive for giving an undercoat 
of Syricum is the evident saving of expense, which results 
therefrom.” He has previously, in another passage, told us 
that the more expensive colours were furnished to the painters 
hy the employers, and says—“ Minium in another w^ay aflPords 
a very convenient opportunity to painters for pilfering hy wash¬ 
ing their brushes filled with colouring matter, every now and 
then. The minium of course falls to the bottom, and is thus 
so much gained to the thief.” 
In the description of these substances there is evidently some 
confusion between these several modifications of minium and 
cinnabar or vermillion, which was both known and used by the 
Pomans. 
The remaining pigment which I examined was of a rose 
colour. I have had with this specimen great trouble to deter¬ 
mine its composition, and I am not as yet thoroughly satisfied 
regarding its exact nature. The outer portion exposed to the 
air is of a cream colour, but the interior has a rose tint. It 
consists of a fine white clay with chalk and some colouring 
matter. Having satisfied myself that this colouring matter was 
not mineral but of organic origin, I endeavoured to ascertain 
with what colours derived from this source, and known to the 
Pomans, the pigment in question corresponded. 
The Porfura of the Greeks, and the Purpurissimum of Pliny 
was a colouring matter derived from species of shell fish belong¬ 
ing to the genera Murex and Purpura. Yitruvius says that 
the fish from the northern countries afforded a more violet, and 
those from the southern coasts a redder colour, and Pliny says, 
that for the use of painters, ‘‘ argentine creta ” was dyed with 
it. 
It is necessary here to remark that the antients do not 
appear to have been acquainted with the difference between 
calcareous and aluminous earths, and that “ creta ” was a term 
applied by them to every fine white earthy powder. Both 
Yitruvius and Pliny say that in reference to this particular 
instance, it was adulterated or imitations made of it by 
