BOTANICAL SOCIETY OF CANADA. 
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applications of Sticta pulmonaria in the arts. Insignificant and apparently trifling as 
Lichens are, yet some of them yield products that render them very valuable in the 
arts. Dyes are the more important products at present obtained from them, though 
there is no doubt, now that attention is being more directed to them by scientific 
men, and that Chemistry is making such rapid progress, they will be found to pos- 
sess many properties hitherto unknown to science — properties that will render 
them exceedingly useful from their contributing to the comforts or necessities of 
man. An advance has been made even within the last few years, several species 
having been found to yield dyes quite as valuable as those obtained from Rocella 
tinctoria, or Lecanora tartarea. Sticta pulmonaria, although not, at the present 
time, ranked among those Lichens which are thus important as furnishing some par- 
ticular product, yet has properties that, in many respects, attach to it considerable 
interest. For instance, the bitter principle contained in it has, in Sweden and 
Siberia, been applied to the purposes of the brewer as a substitute for hops. The 
Monks of a certain Monastery in the latter country acquired quite a reputation for 
the beer which they brewed, they having been accustomed to flavor it with the 
bitter principle of this species of Sticta. Again, the tanner has made it subservient 
to his purposes. The astringent principle which it contains, and which renders it 
valuable to the tanner, is most likely due to the presence of tannic acid. However, 
even were this Lichen an efiicient substitute for the bark of the Oak, Sumach and 
other trees which are employed in tanning, it could not be obtained in sufficient 
abundance to meet the probable demand for it. This fact, too, would, I think, be 
an efi"ectual bar to its use in brewing, as a substitute for hops. It might, certainly, 
be propagated by artificial means, but, as it has not yet been proved that Lichens 
are undestructive to trees, such a proceeding, whilst beneficial in one way^ might 
prove detrimental in another. The most valuable property of this Sticta, and 
which has been the most largely applied in the arts, is its capability of yielding a 
brownish colouring matter. There are several ways in which this dye may be 
obtained. The Lichen may be macerated in milk of lime, and its colorific princi- 
ples precipitated by the addition of hydrochloric or acetic acid. Or, it may be 
steeped in a solution of carbonate of soda for several days. But the most simple 
method, and which most fully developes the colouring matter, is by ammoniacal 
maceration. Previous to being macerated in the solution, the plant should be care- 
fully cleansed from earthy and other extraneous substances, which are generally 
found adhering to it, and then pulverized. The liquid, after the Lichen has been 
placed in it, should be frequently stirred in order that every part may be well 
exposed to the action of the oxygen of the atmosphere. If submitted to the above 
process for a period of about ten days, Sticta pulmonaria yields a very good brown 
dye, which has been, and is still, to a great extent, applied to the dyeing of various 
woolen goods by the peasantry of Norway and Sweden, and other countries. In 
