118 FIRST STEPS IN GENERAL KNOWLEDGE. 



from the air, and are covered with little pores or 

 mouths, invisible to the naked eye. Some of the 

 species, when boiled in milk, are eaten by country 

 people, and are considered cooling and wholesome. 

 The Greenlanders use one of the tribe* as food ; 

 but the common biting stoiiecrop, or wall-pepper,-f- 

 which is so abundant in this neighbourhood, acts 

 on many constitutions as an emetic. It is with the 

 fresh leaves of a houseleekj that thf! fishermen of 

 Madeira rub their nets, which are thus rendered 

 as durable as if tanned, being also steeped in some 

 alkaline liquor." 



" It is a good thing that some of the houseleeks 

 are wholesome," said Eobert, " because they grow 

 where nothing else can grow ; and I dare say the 

 poor Greenlanders are very glad with vegetable 

 food, and so must the people be who have to cross 

 sandy plains and deserts." 



" It is a wonderful provision of the Almighty," 

 said his father, "that these humble plants should 

 be able to bear the extremes of heat and cold, and 

 to flourish in situations where our hardiest mosses 

 would be destroyed." 



* Rhodiola rosea. f Sedum acre. 



J Sempervivum glutinosum* 



