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 and hygroscopic properties as by the nitrogen 

 which they contain. Salmon uses then), after 

 having been dried in the sun and powdered, 

 for the disinfection of faecal matters, with 

 which, in a dry state, they form an excellent 

 manure, containing 2.4 per ct. of nitrogen. 



Sea-weeds. In England, Scotland, and Ire- 

 land, they use, under this title, the different 

 plants of the alga family. The harvest is 

 made from the surface of rocks and at the 

 bottom of the sea with large hoes and rakes. 

 There are certain regulations peculiar to each 

 locality, as to the time and mode of harvest. 

 This manure, rich in salts of soda and potassa, 

 has the great advantage of being entirely ex- 

 empt from injurious seeds. The different fuci, 

 after being drained, have 0.75 of nitrogen; 

 dried in the air, they still retain 0.40. In this 

 state the Fucus saccharinus possesses 1.38 

 per ct. of nitrogen, and the Fucus digitatus 

 0.86 only: completely dried, the first holds 

 2.29, and the second 1.41. The burnt sea- 

 weed contains 0.40 of nitrogen. 



The aquatic plants of fresh waters are also 

 applicable as manure. 



Reeds. Reed is the most used of fresh wa- 

 ter plants. When mowed green it readily 



