Loess

Aiton's Encyclopedia (1910)

lo'es, in geology, a loamy deposit in the valley of the Rhine. It is an exceedingly fine, yellow, silty loam, uniform in character from top to bottom, and showing hardly any signs of stratification. There are, in places, fresh water shells and bones of animals. The term has been extended to formations of similar appearance elsewhere. A vast area in northern China is covered by a loess formation through which rivers have worn valleys of great depth. Authorities assert that the loess of China is nothing less than a vast plain of fine dust carried by the winds from Central Asia. The origin is a geological puzzle. Wherever found, loess has a special ability to stand in upright walls; and yet it is so mellow that it can be crushed between the thumb and forefinger. Where it occurs it is always the most recent formation. Loess occupies several thousand square miles in the drainage basin of the Mississippi. The American loess is thought to be the product of glacial action, being a deposit of silt carried southward by streams flowing from the towering glacial mass of the northern ice cap. This North American loess extends from Dubuque southward, and is from five to 150 feet deep. It is composed of exceedingly fine, sharp-angled particles indicating an origin by chipping and crushing rather than a chemical origin, or decomposition of rock material. It is almost true that this loess contains a little of everything, for it is composed of at least sixteen elements. Silicon is present in silica, which forms from sixty to seventy-three per cent of the whole; aluminum is present in alumina, which forms from eight to twelve per cent; other compounds present are iron particles, lime, soda, potash, magnesia, and water. There are traces of carbon and sulphur. This soil is amazingly fertile when supplied with nitrogen. Lofoden (lo-fo'den) Islands, a chain of islands on the western coast of Norway. The chain flanks the mainland. It has been compared to a backbone which tapers away to the small vertebra of the tail to the south. At a distance the chain looks like a slender peninsula. There are many bays and straits and rocky islets. The shores are steep; the mountains are picturesque. Some of them are covered with snow, others with green moss. There are many good harbors and fishing villages where large vessels "dwarfed to nut shells, lie close to rocks several hundred feet high." The Lofoden Islands are noted chiefly for the codfishery which is carried on from the middle of January to the middle of April. At this season the cod come from the depths of the Atlantic to spawn. Forty thousand fishermen and 9,000 boats float to the Lofoden harbors and establish themselves in the fishing centers. Both nets and hooks are used. Storms not infrequently catch the fishermen in exposed situations and drive them away or capsize them. The fish are salted and dried. The heads are converted into fish guano. The spawn is sold for sardine bait. Cod-liver oil is made from the liver. Bergen is the market town. See Bergen