738 



L I C II E N. 



In medi- 

 cine. 



Lichen, alcohol ; but the taste of this, is not discernible in the 

 "Y""""' water in which they are boiled. Some others of the 

 branched and filamentous lichens, such as Ramalina 

 fraxinea and fastigiata, and Usnea barbata, have been 

 examined chemically by Berzelius, and found to be 

 characterized by the presence of a species of starch 

 possessing several peculiar properties. Probably these 

 also might be employed as food. 



Medicine. Several of the lichens were formerly ce- 

 lebrated as specifics in the cure of diseases. The com- 

 mon cup-moss (Lichen pyxidatus, or Cenomyce pyxi- 

 data, Ach.) was long regarded as an infallible nostrum 

 for the hooping-cough. The common ground liver- 

 wort (Lichen caninus, or Peltidea canina, Ach.) receiv- 

 ed its trivial name on account of the fame it had ac- 

 quired as a specific for the bite of a mad dog. Even 

 the celebrated Dr. Mead, in his History of Poisons, eu- 

 logized this medicine, and declared that it had never 

 failed, during thirty years experience, in averting the 

 terrible consequences which result from the bite of this 

 animal when in a rabid state ; but at the same time he 

 mentioned, that copious bleeding was to be conjoined. 

 The tree lungwort or oak-lungs (Lichen pulmonarius, or 

 Sticta pulmonacea, Ach.) was renowned in former times, 

 for relieving pulmonary complaints. In those days, 

 nothing was more common among practitioners who 

 trusted in simples for the cure of diseases, than en- 

 deavouring to find a plant possessed of some fancied re- 

 semblance to the part of the body affected : the wrinkled 

 and reticulated frond of this lichen having some simi- 

 larity to the surface of the human lungs, there remain- 

 ed no question of the propriety of administering it for 

 disorders of these organs. It is scarcely necessary to 

 add, that it has now completely lost its fame as a speci- 

 fic. From the experiments of Georgi and Amoreux, 

 however, it appears, that this species possesses a por- 

 tion, equal to one-eighth of its substance, of a reddish 

 gum, having a slightly bitter taste : it is one of those, 

 therefore, which may deserve the attention of the phar- 

 macologist. The Iceland mow, as already hinted, has been 

 recommended in incipient consumptive cases in this 

 country, and a Decoctum Lichenis Islandici has a place in 

 the Edinburgh Phan/tacopoeia. It is generally consi- 

 dered, however, as scarcely otherwise useful, than as af- 

 fording a light nourishing diet. In Iceland and in Swe- 

 den it is much employed as an evacuant in the spring sea- 

 son. Dr. Withering tells us, that the country people in 

 England make an infusion of Lichen aphthosus ( Peltidea 

 aphthosa, Ach.) in milk, and give it to children affected 

 with the thrush, (aphthae in themouth,) and that, in large 

 .dozes, it destroys worms, by exciting purging and vo- 

 miting. Linnaeus informs us, that the Laplanders ap- 

 ply a bandage composed of tree-moss, (Usnea plicata, 

 Ach.) to their feet, when excoriated with travelling, 

 and that they find great benefit from this kind of cata- 

 plasm, arising probably from the styptic quality of the 

 plant. According to Pontoppidan, the yellow filamen- 

 tous lichen, (Evernia vulpina,) is so poisonous, that 

 it is employed for killing wolves, a carcase of some 

 animal, smeared and stuffed with the powder of it, mix- 

 ed with pounded glass, being set as a bait. It may be 

 remarked, that a lichen, said to possess the active and 

 powerful properties of a poison, might deserve further 

 examination, as more likely to prove useful, when skil- 

 fully regulated by the physician, than such species as 



Uses of li- have not attracted notice by exerting any remarkable 



C S rtT s in the energy. 



In perfume- Perfumery. Lichens have for a long time been em- 



jy. ployed in perfumery. It is now impossible, perhaps, 



to determine with certainty what the vsnea of the an- Lichen. 

 cients was, or whether it even belonged to Ihe family N V""*' 

 of lichens. According to Dillenius and Ray, '^ was a 

 filiform lichen, found on trees in the East Indies, and 

 which, when moistened, exhaled an odour of musk or of 

 ambergris. It is enrolled by Acharius under the name 

 of Alectoria Arabum, but it must be regarded as merely 

 a conjectural species. In the seventeenth century, some 

 of the filamentous lichens were undoubtedly kept in 

 shops, under the name of Usnea ; and they formed the 

 basis of a noted perfume called corps de Cypre gris, or 

 pulvis Cypritts. Their employment for this purpose, 

 however, did not probably depend on any remarkable 

 inherent scent, but on their aptitude for imbibing and 

 retaining odours. Lichen prunastri (Evernia prunas- 

 tri, Ach.) is, in fact, as well adapted for this purpose, 

 though nowise fragrant ; and to this day this species 

 forms the basis of several perf>cd powders. 



Dyeing. Various species of lichen have long been In dyeing. 

 used by the common people in the northern countries 

 of Europe for communicating different tints to cloths 

 of home manufacture. These are generally of coarse 

 wool, and the process of dyeing them is proportionally 

 rude. Several species, however, have likewise been 

 employed by artists, and from these the colour has 

 been extracted with the care and skill of the practical 

 chemist. See article DYEING. 



The orchal, or archil, (Roccella tinctoria) is the OrchL 

 most valuable lichen as a dye-stuff. If we may trust 

 to Tournefort, the properties of this species were t'a- 

 miliar to the ancients ; it was collected in the islands 

 of the Archipelago, and, from one of these, acquired 

 the name of Purple of Amorous. In modern times, ac- 

 cording to Berthollet, it was first prepared as an ar- 

 ticle of commerce at Florence, the fine violet colour 

 which resulted from mixing it with urine having been 

 accidentally observed by a Florentine merchant, about 

 the year 1300, while visiting the Levant. The li- 

 chen, reduced to powder, is put into a vat with urine 

 and quicklime, and frequently stirred, additional por- 

 tions of these substances being added, till the mixture 

 have acquired the desired tint. Orchal, thus prepared, 

 yields a purple or purplish-red colour, which is not 

 however easily fixed. The alcohol in spirit thermome- 

 ters is usually tinged with orchal, and will afford to 

 the reader an idea of the tint commonly produced. It 

 is sometimes employed, and with great success, for 

 brightening other colours. The lichen grows very 

 abundantly on the sea rocks of the Cape Verd, and 

 also of the Canary Islands, and from both clusters it 

 is exported in considerable quantities. About the 

 year 1750, not less than 100 tons were annually col- 

 lected in these islands. In the English market, it is 

 at present (1818,) worth about 200 per ton, the price 

 varying, to the extent perhaps of <tl40 a ton, according 

 to the quality of the need, as the merchants call.it. 

 The plant occurs, but sparingly, on the sea-rocks of the 

 south of England. In France it is called orseille, and 

 is used to a considerable extent, in the southern pro- 

 vinces, for dyeing silks, being collected on the rocky 

 shores of the Mediterranean. By the Dutch it is manu- 

 factured into a paste called by them Lacmus or Litmus. 

 This is sold in square masses about an inch in length, 

 and half an inch in breadth and thickness, hard and 

 brittle, having the appearance of a violet-coloured earth, 

 with white spots. It may here be remarked, that ano- 

 ther species of Roccella, R. fuciformis, is reported to vie 

 in richness of colouring matter with the common or- 

 chal, while the plant attains to a much larger size. 



