Narrative of the surveying voyages of his majesty's ships Adventure and Beagle (vol.2): between the years 1826 and 1836 : describing their examination of the southern shores of South America, and the Beagles's circumnavigation of the globe

GRASS — SOIL POTASH. S57 southern half of East Falkland, whore, as I mentioned, the soil is good, there is abundance of long, but brownish grass over all the country, and at the roots of it there are sweet tender shoots, sheltered from the wind, much liked by cattle. In that district there are several varieties of grass growing on fine dark-coloured earth, mixed with light white sand ; and, although, from never being cut, it has a rugged and brown appearance, its nutritive properties must be considerable, as the finest cattle are found feeding there. Mr. Bynoe remarked to me, that wherever the surface of the ground had been broken by cattle, he found a very dark-coloured earth mixed with sand or clay, or else clay mixed with gravel and sand. That the clay is good for bricks has been mentioned ; but I have not said that there is stone of two or three kinds suitable for building, and that any quantity of lime may be obtained by burning fossil shells brought from the coast of Patagonia, where the cliffs are full of them, or by collecting the shells scattered upon the Falkland shores. Another natural produc- tion, of more value than it has hitherto been considered, is the common sea-weed or kelp ; * and I am told by Sir Woodbine Parish that the archil or orchilla weed was obtained there by the Spaniards. It is to be remarked, that the soil of East Falkland has been very much improved in the neighbourhood of the settlement, as well as around the estancia, or farm, where the tame cattle are kept, in consequence of the treading and manuring it has • The manner of extracting potash from sea-weed is as follows : When a sufficient quantity of kelp has heen collected, it is spread out in a place where it will be dried by the sun and wind, and when dry enough to burn, a hollow is dug in the ground three or four feet wide ; round its margin are laid stones, on which the weed is placed and set on fire. Quantities of this fuel being continually heaped upon the circle, there is in the centre a constant flame, from which a liquid substance, like melted metal, drops into the hollow beneath. This substance is worked, or stirred, with iron rakes, and brought to an uniform consistence while in a state of fusion ; and when cool, it consolidates into a heavy, dark- coloured alkaline substance, which undergoes in the glass-houses a second vitrification, and then assumes a perfect transparency. VOL. II. S