Page:Popular Science Monthly Volume 36.djvu/394

380 grow, as well as the number of iodine-bearing plants, are very limited. The shores of the British Isles and of Brittany are the spots most favored, owing to the presence of the Gulf Stream, which serves as the carrier of the iodine and of the temperature conditions necessary to the growth of the Algæ.

By far the larger portion of the sea-weed harvest comes ashore in the early spring and in the late fall. The fall harvest, together with that which winter adds, is suffered in most localities to lie untouched on the beach until it has been carried out to sea again and lost forever. It is only the spring crop which receives special care. Thousands of women and children, and a small sprinkling of men, may be seen flocking to the beach during the month of May, armed with rakes and wheelbarrows, or driving low carts, whose wheels are made broad enough to prevent their sinking in the sand. The wet weeds are raked into piles, and carried either by barrow or cart to a conveniently safe distance from the water's edge. Usually a sheltered nook is chosen, if near at hand, and in it is stored a great mass of the weed. Here it is left to dry under the summer 's hot sun, meanwhile exhaling odors of no dainty description. There are well-recognized liberties and restrictions in regard to sea-weed accorded to landlords and peasantry who dwell along the shore. The landlords have most of the liberties, while the peasants enjoy the restrictions. Conflicts of sea-weed rights have been known to occur, in which cases the shillalah has had an important share in the gathering of the crop.

When the weed is dry—that is, in the latter part of July and the first of August—the owners of the sea-weed heaps undertake to burn them into kelp. This burning is done in the crudest and most wasteful manner. Shallow pits, often dug right in the sand, are filled with weed and the mass ignited. Upon the first charge fresh quantities of weed are thrown from time to time, the whole mass burning more or less rapidly in proportion to the dryness of the weed. There results, in the bottoms of these pits, a black mass resembling iron-slag in appearance, though not in hardness, which, being sprinkled with water while hot, breaks up into large lumps suitable for transportation. Owing to the carelessness with which the weeds are raked up, this crude kelp-slag always contains a large percentage of sand and other impurities, sometimes amounting to one half the total weight of the product. The improvidence of this is the more marked in view of the small amount of valuable salts which even at best can be found in the kelp, and the rapid ratio in which the cost of transportation diminishes the profits when half of the slag is dead weight. The improvidence extends equally to the burning itself. This takes place in full access of air, and at a temperature so high as to volatilize much of the iodine. Besides, all the gaseous products of the