98 FOOTNOTES FROM 



the meal obtained from it, when mixed with wheat-flour, 

 produces a greater quantity of bread, though perhaps of 

 a less nutritious quality, than could be manufactured 

 from the latter alone. The extremely bitter taste, how- 

 ever, by which it is characterized, owing to a peculiar 

 astringent principle in it called cetrarin, which has been 

 procured in a state of purity, in the form of a white 

 powder like magnesia, by Herberger, has always proved 

 a great drawback to its adoption as an independent 

 article of food, especially in this country. In Iceland 

 and Lapland, however, the inhabitants remove this dis- 

 agreeable quality by a very simple process. They first 

 chop it to pieces, and macerate it for several days in 

 water mixed with salt of tartar or quick-lime, which it 

 absorbs very freely ; it is then dried and reduced to 

 powder, and mixed with the flour of the common knot- 

 grass, made into a cake or boiled, and eaten with rein- 

 deer's milk, and eaten with relish, too, by these poor 

 people, who confess, with a most simple and affecting 

 gratitude, that " a bountiful Providence sends them 

 bread out of the very stones." The powder is not unlike 

 starch in appearance, and possesses some of its proper- 

 ties, for it swells in boiling water, and becomes, on cool- 

 ing, a fine jelly, which soon hardens into a tough, trans- 

 parent substance, very pleasant to the taste, especially 

 when flavoured with sugar, milk, a little white wine, or 

 aromatics. It is frequently used for making blanc-mange 

 in this country, for which purpose it is said to be equal, 

 if not superior, to Irish moss or the finest isinglass. The 

 bitter principle is often used for brewing, and in the com- 

 position of ship-biscuit, to prevent the attack of worms. 



