DYEING PROPERTIES OF LICHENS. 69 
to the pages of the ‘ Phytologist.’ It may be of some commer- 
cial importance, and it is of great interest both to art and science. 
Most botanists are aware that Lichens possess colorifie proper- 
ties, some more, some less; and also that several of them are 
already employed in the preparation of some of our most impor- 
tant and permanent dyes. With this brief preamble, we intro- 
duce Dr. Lindsay to our readers, with an earnest wish that this 
may not be both his first and last appearance as a contributor to 
this periodical.* The author states that having “on former oc- 
casions so fully occupied the time of the Society [the present is a 
résumé of a series of communications made to the Botanical So- 
ciety of Edinburgh in the years 1852, 1853, and 1854. We 
wish the Society would now and then send us a copy of their 
published proceedings, and we would do our best to give pub- 
licity to their discoveries,| with detailed views on this subject,” 
he confines himself “to a few facts explanatory of the tables.” 
These are— 
I. Certain genera and species of Lichens abundant in Scotland might 
at a very moderate expense be collected, and serve as substitutes for the 
foreign Lichens used in the manufacture of orchil, cudbear, and litmus. 
II. This subject is deserving of the manufacturer’s notice on the one 
hand, and the chemist’s on the other. 
a. On account of scientific interest, the subject being new and pro- 
mising. 
6. With the view of developing the economic resources of our own 
country. 
e. The result promises to be remunerative, as Roccelias have reached 
the high price of £1000 per ton in the London market. 
V. The Lichens richest in colorific principles are crustaceous and foli- 
aceous species, of a pale or whitish colour. These grow on rocks or 
stones, In mountainous countries and on sea-coasts. 
XII. The chief tint educible from Lichens which can be of any perma- 
nent utility in the arts, is ved; brown is also useful in a minor degree. 
The solvents employed for the extraction of the colouring mat- 
ters of these plants, the Doctor states, are chloride of lime, al- 
cohol, ammoniac water, and water alone; and the time employed 
in these solutions varied from a few hours to a few months. The 
* Our present number contains a paper on the Flora of Dumfries and its vici- 
nity. We believe the author of this interesting account is also the author of these 
experiments and results. We should like to meet with Dr. Lindsay in either cha- 
racter, either as a botanist or as a chemist. 
