e leaves of the sweet willow, _salix pentandra_,
gathered at the end of August and dried in the shade, afford, if
boiled with about one thirtieth potash, a fine yellow colour to wool,
silk and thread, with alum basis. All the 5 species of Erica or heath
growing on this island are capable of affording yellow much like those
from the dyer's broom; also the bark and shoots of the Lombardy
poplar, _populus pyramidalis_. The three leaved hellebore, _helleborus
trifolius_, for dyeing wood yellow, is used in Canada. The seeds of
the purple trefoil, lucerne, and fenugreek, the flowers of the French
marigold, the camomile, _antemis tinctoria_, the ash, _fraxinus
excelsior_, fumitory, _fumaria officinalis_, dye wool yellow." "The
American golden rod, _solidago canadensis_, affords a very beautiful
yellow to wool, silk and cotton upon an aluminous basis." _Bancroft._]

CHAPTER IV

THE LICHEN DYES

Some of the most useful dyes and the least known are to be found among
the Lichens. They seem to have been used among peasant dyers from
remote ages, but apparently none of the great French dyers used them,
nor are they mentioned in any of the old books on dyeing. The only
Lichen dyes that are known generally among dyers are Orchil and
Cudbear, and these are preparations of lichens, not the lichens
themselves. They are still used in some quantity and are prepared
rather elaborately. But a great many of the ordinary lichens yield
very good and permanent dyes. The _Parmelia saxatilis_ and _Parmelia
omphalodes_, are largely used in the Highlands and West Ireland, for
dyeing brown of all shades. No mordant is needed, and the colours
produced are the fastest known. "Crottle" is the general name for
Lichens in Scotland. They are gathered off the rocks in July and
August, dried in the sun, and used to dye wool, without any
preparation. The crottle is put into the bath with a sufficient
quantity of water, boiled up, allowed to cool, then boiled up with the
wool until the shade required is got. This may take from one to three
or four hours, as the dye is not rapidly taken up by the wool. Other
dyers use it in the following way: A layer of crottle, a layer of
wool, and so on until the bath is full; fill with cold water and bring
to the boil, and boil till the colour is deep enough. The wool does
not seem to be affected by keeping it in the dye a long time. A small
quantity of acetic acid put with the Lichen is said to assist in
exhaust