34 INTRODirCTION. IV. 



finest of wliicli sell for their weight in gold, and enter into the composition of the 

 most luxurious Chinese dishes, were constructed of the semi-decomposed branches 

 of some Alga of one or other of the above named genera ; but it has since been 

 ascertained that these nests consist of an animal substance, which is supposed to be 

 disgorged by the swallows that build them. 



Nearly all the cartilaginous kinds of Rhodospermeee will boil down to an edible 

 jelly. One kind is preferred to another, not from being more wholesome, but from 

 yielding a stronger and more tasteless gelatine. The latter quality is essential ; for 

 though the skill of the cook can readily impart an agreable flavour to a tasteless 

 substance, it is more difficult to overcome the smack of an unsavoury one. And 

 the main quality which gives a disrelish to most of our Algte-jellies and blanc- 

 manges, is a certain bitterish and sub-saline taste which can rarely be altogether 

 removed. 



Yery few Algae have been found agreeably tasted when cooked, though DilUsk 

 and others are pleasantly sweet when eaten raw. Many which, when moistened 

 after having been dried, exhale a strong perfume of violets, are altogether disap- 

 pointing to the palate. 



Perhaps, after all, the most valuable as articles of food are the varieties of Por- 

 phyra vulgaris and P. laciniata, which in winter are collected on the rocky shores 

 of Europe, and by boiling for many hours are reduced to a dark brown, semi-fluid 

 mass, Avhich is brought to table under the name of marine sauce, sloke, slouk, or 

 sloucawn. It is eaten with lemon juice or vinegar, and its flavour is liked by most 

 persons who can overcome the disgust caused by its very unpleasant aspect. At 

 some of the British establishments for preserving fresh vegetables, it is put up in 

 hermetically sealed cases for exportation and use at sea, or for use at seasons when 

 it cannot be obtained from the rocks. It is collected only in winter, at which 

 season the membranous fronds, which are found in a less perfect state in summer, 

 are in full growth. Both species of Porpliyra grow abundantly on the rocky shores 

 of North America. They not only furnish an agreeable vegetable sauce, but are 

 regarded as antiscorbutic, and said to be useful in glandular swellings, perhaps from 

 the minute quantity of iodine which they contain. 



As articles of food for man, other seaweeds might be mentioned, but I admit that 

 none among them furnish us directly with valuable esculents ; though many less 

 nauseous than the hunter's " Tripe de Roche" are sufficiently nourishing to prolong 

 existence to the shipwrecked seaman ; and others, like the PorpliyrcB just men- 

 tioned, are useful condiments to counteract the efiects of continued subsistence on 

 salt-junk. 



But if not directly edible, there are many ways in which they indirectly supply 

 the table. As winter provender for cattle, some are in high esteem on the northern 

 shores of Europe. In Norway and Scotland the herds regularly visit the shores, on 

 the recess of the tide, to feed on Fucus vesiculosus and F. serratus, which are 

 both also collected and boiled by the Norwegian and Lapland peasants, and when 

 mixed with coarse meal given to pigs, horses, and cattle. These Fuci are both 

 grateful and nourishing to the animals, which become very partial to such food. 

 Yet, perhaps, they are only the resources of half-fed beasts, and would possibly be 



