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to their sufferings. Let us hope that no more valuable 

 lives will be sacrificed to the love of science and adven- 

 ture in these terrible regions ; the numerous expeditions 

 undertaken in recent times having taught us the limit of 

 human endurance, if they have done nothing else. 



The tripe de roche consists of various species of Gyro- 

 phora black, leather-like lichens, studded with small 

 black points like coiled wire buttons, and attached by an 

 umbilical root, or by short strong fibres to rocks on the 

 mountains. Some of them bear no unapt resemblance to 

 a piece of shagreen ; while others appear corroded, like 

 a fragment of burnt skin, as if the rock on which they 

 grew had been subjected to the action of fire. They are 

 found in cold exposed situations on Alpine rocks of granite 

 or micaceous schist, in almost all parts of the world on 

 the Himalayas and Andes as well as the British moun- 

 tains ; but it is in the Arctic regions alone that they 

 luxuriate, covering the surface of every rock, to the 

 level of the sea-shore, with a gloomy Plutonian vegetation, 

 that seems like the charred cinders and shrivelled re- 

 mains of former verdure and beauty. Though they con- 

 tain a considerable quantity of starch, they are exceedingly 

 bitter and astringent, and produce intolerable griping 

 pains when eaten. No one would have recourse to them 

 for food except in a case of dire necessity. The Canadian 

 hunters who are often reduced to the last extremity, 

 during their long and toilsome excursions in search of 

 furs, through the desolate regions of Arctic America, 

 often allay the pangs of hunger with this nauseous diet. 

 And sometimes in my own wanderings among the almost 

 unknown and unvisited solitudes of the Scottish moun- 



