THE SEA-SHORE. 171 



it emits when heated. Polished plates of silver 

 held over these fumes are peculiarly sensitive of 

 light, and are used in taking likenesses by the pro- 

 cess called the Daguerreotype. 



Some species also contribute to the comfort of 

 man, by supplying him with food. The " Carrageen 

 Moss,"* sold in druggists' shops, is nothing more 



CARRAGEEN MOSS. 



than dried sea-weed, growing abundantly on most 

 of our coasts. Another speciesf is stewed, and, 



* Chondrus crispus. f Porphyra laciniata. 



