Purpŭra
(
πορφύρα). The finest and most costly dye of the ancients,
a discovery of the Phœnicians, though known to the Greeks in the Homeric Age. This
may be inferred from the frequent epithet
πορφύρεος applied
to robes, rugs, etc. It was also known to the Romans in the time of their kings. It was
obtained from two kinds of shells in the Mediterranean Sea:
- 1. from the trumpet-shell (Gr. κῆρυξ; Lat. bucinum, murex);
- 2. from the true purple-shell (Gr. πορφύρα; Lat. purpura, pelagia=murex brandaris or tribulus).
These shells respectively contained in a diminutive bladder a small quantity of
- 1. scarlet-coloured,
- 2. black-and-red-coloured juice.
The juice collected from a number of these shells was placed in salt in the proportion
of about one pint of salt to every seventy-five pounds avoirdupois of juice, and heated in
metal vessels by the introduction of warm vapours; then the raw material, wool and silk, was
dyed in it. The best and dearest purple was always the Phœnician, especially that of
Tyre, although it was prepared by other inhabitants of the Mediterranean. As the colour of the
bucinum was not lasting, it was not used by itself, but only in
combination with the true purpura for producing certain varieties of purple dye. By mixing
bucinum with black
pelagium, the juice of the true
purple-shell, the fashionable violet, called the “amethyst” purple, was
produced; and, by a double process of dyeing, first in half-boiled
pelagium, and then in
bucinum, Tyrian purple was produced. This
had the colour of clotted blood, and when looked at straight appeared black, but when held to
the light it glowed with colour. A pound of violet wool cost in Caesar's time 100
denarii ($20), Tyrian purple wool above 1000
denarii
($200). By mixing
pelagium with other matter— water,
urine, and orchilla—the bright purple dyes —heliotrope-blue, mauve-blue,
and violet-yellow —were obtained. Other colours were produced by the combination of
the different methods of dyeing; first dyeing the material with violet colour, purple dye, and
scarlet (produced from the
coccus ilicis); then by using the Tyrian
method they obtained the
tyrianthinum, the Tyrian shell-purple, and the
variety called the
ὕσγινον, from
ὕσγη, a variety of
πρῖνος, or
quercus coccifera (Pliny ,
Pliny H. N. ix.
124-141). The native dye was apparently not easily distinguished from the Tyrian when
newly applied, except by the connoisseur (
Epist. i. 10, 26-30). For further
details, see Blümner's
Technologie, i. 224-240.
Purple robes were used at an early date by the Greeks as a mark of dignity. Even the
Athenian archons wore purple mantles officially. In Rome at one time broad, at another narrow,
stripes of purple on the toga and tunic served as marks of distinction for senators,
magistrates, and members of the equestrian order. The robes of the general were dyed in purple
(see
Paludamentum); so also was the
gold-embroidered mantle worn by one who celebrated a triumph. For a long time home-purple was
used; Tyrian purple was not introduced till the middle of the first century B.C., and from
that time it became a luxury. In spite of repeated attempts to check by imperial decrees the
use of real purple among private individuals, robes trimmed with purple, or altogether dyed
with it, became more and more used. Only a complete robe of
blatta, the
finest kind of purple, of which there were five varieties, was reserved as an imperial
privilege, and any private person who wore it was punished as being guilty of high-treason
(
Cod. Theod. iv. 40, 1). From the second century A.D. the emperors took part
in this lucrative industry, and from the end of the fourth century A.D. the manufacture of the
blatta became an imperial monopoly.