THE PRINCIPLES OF BOTANY. 
845 
islands of the Indian Archipelago, have much the same pro¬ 
perties as the carrageen. 
Mr. Crauford says, It is exported to China by the islands 
of the Indian Archipelago, and forms a portion of the cargoes 
of all the junks, the price on the spot where it is collected 
seldom exceeding from 5s. Sd. to 7s. 6^d. per cwt. The 
Chinese use it in the form of jelly with sugar, as a sweet¬ 
meat, and apply it in the arts as an excellent paste. The 
gummy matter which they employ for covering lanterns, 
varnishing paper, &c., is made chiefly, if not entirely, from it.’^ 
As a rule the fuci contain important chemical matters, and 
hence burnt sea-weeds are employed for the production of 
both potash, soda, and the highly valuable element iodine. 
Vegetable ethiops,” prepared by incinerating Fucus 
vesiculosus in a covered crucible, was at one time used in the 
same manner as burnt sponge. According to Professor 
Lindley, whatever medical value they possess seems to be 
owing to the presence of iodine, which may be obtained 
either from the plants themselves or from kelp. French 
kelp, according to Sir Humphrey Davy, yields more iodine 
than British; and, from some experiments made at the Cape 
of Good Hope, Ecklonia huccinalis is found to contain more 
than any European sea-weed. Iodine is known to be a 
powerful remedy in cases of goitre. The burnt sponge, for¬ 
merly administered in similar cases, probably owed its efficacy 
to the iodine it contained; and it is also a very curious fact 
that the stems of a sea-weed are sold in shops, and ehewed 
by the inhabitants in South America, wherever goitre is pre¬ 
valent, for the same purpose. The remedy is termed by them 
palo coto^’ (literally goitre-stick), and consists of fragments 
of the Sargassum hacciferum and Laminarias. Iodine is 
principally obtained in Europe from the ashes of the Fuci 
vesiculosusy nodosus, ceranoides, and serratus.* 
Iodine is much employed in veterinary treatment, espeeially 
in the forms of biniodide of mercury and iodide of potassium; 
and its effects in glandular tumours are said to be very marked. 
In Sweden and Norway many sea-weeds are used as food 
for stock, for which it is probable that they may he employed 
to profit in this respect at home, to which end, as their 
quantity is so large, they deserve a more extended study 
and examination than they have yet received. 
As manure sea-weeds will always be of value, if only for 
their contained alkalies, for which our table may be con¬ 
sulted, and in so employing them it will he seen that their 
* See the ‘ Vegetable Kingdom.’ 
