LICHENS IN INDUSTRY 411 



D. LlCHEMS USED IN TANNING, BREWING AND DISTILLING 



The astringent property in Cetraria islandica and in Lobaria pulmonaria 

 has been made use of in tanning leather. The latter lichen grows commonly 

 on oak and could hardly be gathered in sufficient quantity to be of com- 

 mercial importance. Like many other lichens it develops very slowly. 

 Lobaria pulmonaria has also been used to replace hops in the brewing of 

 beer. Gmelin' in his journey through Siberia visited' a monastery at Ussolka 

 where the monks employed it for this purpose. The beer tasted exactly 

 like that made with hops, but was more intoxicating. The lichen in that 

 country grew on pine-trees. 



Lichens have in more modern times been used in the preparation of 

 alcohol. The process of manufacture was discovered by Roy of Tonnerre, 

 early in the nineteenth century, and was described by Ldorier^. It was 

 further improved by Stenberg^, a Professor of Chemistry in Stockholm. 

 Roy had worked with Physcia ciliaris, Ramalina fraxinea, R. fastigiata, 

 R. farinacea and Usnea Jlorida, but Stenberg and distillers after his time-* 

 made more use of Cladonia rangiferina (Fig. 127), Cetraria islandica 

 (Fig. 128) and Alectoria jubata. 



By treatment with weak sulphuric or nitric acid the lichenin of the 

 thallus is transformed into glucose which on fermentation forms alcohol. 

 Stenberg found that 68 per cent, of the weight in Cladonia rangiferina was 

 a " sugar " from which a good brandy could be prepared : a kilogramme of 

 the lichens furnished half a litre of alcohol. The Professor followed up his 

 researches by establishing a distillery near Stockholm. His papers contain 

 full instructions as to collecting and preparing the plants. Henneguy**, 

 writing in 1883, stated that the fabrication of alcohol from lichens was then 

 a large and increasing industry in Sweden. The whole industry seems, 

 however, to have fallen into disuse very soon : Wainio'', quoting Hellbom', 

 states that the various distilleries were already closed in 1884, because of 

 the exhaustion of the lichen in the neighbourhood, and the impossibility of 

 obtaining sufficient supplies of such slow-growing plants. 



E. Dyeing Properties of Lichens 



a. Lichens as Dye-plants. Knowledge as to the dyeing properties 

 of lichens dates back to a remote antiquity. It has been generally accepted 

 that lichen-colours are indicated by the prophet Ezekiel in his denunciation 

 of Tyre: "blue and purple from the Isles of Elishah was that which covered 

 thee." Theophrastus describes certain plants as growing in Crete, and being 



' Gmelin 1752, p. 425. '^ Leorier 1825. ^ Stenberg 1868. ■* Richard 1877. 



i* Henneguy 1883. " Wainio 1887, p. 47. ? Helibom 1886, p. 72. 



