The loesssoil is extremely favourable to agriculture.
Wherever loess is found the peasant can live and thrive.
Another peculiarity of loess in China is that it lends itself readily to the excavation of dwellings for the people.
Although the loess of the great plain and the sand of the desert are still in process of formation, the accumulation of these deposits probably began in the Tertiary period.
The loess is a solid but friable earth of brownish-yellow colour, and when triturated with water is not unlike loam, but differs from the latter by its highly porous and tubular structure.
Its principal habitats are rodent burrows in loess dust and burrows of the desert turtle (Vlasov and Miram, 1937).
Its principal habitat is rodent burrows in loess dust, where it is not infrequently found in the food stores of the host (Vlasov and Miram, 1937).
In this, as also in the preceding case, a bed of brick-earth or loess has been removed from above the gravel.
The gravel here retains the same character, but is perhaps rather less coarse; and above it is a thin bed of marl, which separates it from the loess or brick-earth, which in most places has been removed for use.
Thus at the height of a glacial epoch there would apparently be great storminess in the area where the loess is found, especially in summer.
The cyclonic hypothesis also seems to offer a satisfactory explanation of variations in the amount of loess associated with the several glacial epochs.
Another reason for questioning whether the loess was formed at the end of an inter-glacial epoch is that this hypothesis does not provide a reasonable origin for the material which composes the loess.
The evidence of boreal animals seems to disprove the hypothesis that the loess was formed in the middle of a mild inter-glacial epoch.
These four hypotheses as to the time of origin of loess imply the following differences in its climatic relations.
Instead of normal valleys and consequent prompt drainage such as ought to have developed before the end of a long inter-glacial epoch, the surface on which the loess lies shows many undrained depressions.
The conditions would be almost ideal for eolian erosion and for the transportation of loess by the wind to areas a little more remote from the ice where grassy vegetation had made a start.
Hence arises the hypothesis that the wind obtained the loess from the flood plains of streams at times of maximum glaciation.
The famous loess deposits of China in the lee of the Desert of Gobi are examples.
As the ice continued to retreat the area where loess was deposited would follow at a distance, and thus each part of the gravel pavement would in turn be covered with the loess.
The fact that remains of trees sometimes occur at the bottom of the loess probably means that the deposition of loess extended into the forests which almost certainly persisted not far from the ice.
If loess was formed during typical inter-glacial epochs, or toward the close of such epochs, profound general aridity must seemingly have prevailed in order to kill off the vegetation and thus enable the wind to pick up sufficient dust.
Well, I first came across it in loesscliffs in southern Shensi at an elevation of about 4000 feet above sea.
They grow at the edges of deep loessravines and on the steep, sloping bottom of such ravines.
In northern China an area as large as France is deeply covered with a yellow pulverulent earth called loess (German, loose), which many consider a dust deposit blown from the great Mongolian desert lying to the west.
On loess hillsides in China are thousands of villages whose eavelike dwellings have been excavated in this soft, yet firm, dry loam.
In part the loess seems to have been washed from glacial waste and spread in sluggish glacial waters, and in part to have been distributed by the wind from plains of aggrading glacial streams.
Loess mantles the recently uplifted mountains to the height of eight thousand feet and descends on the plains nearly to sea level.
A yellow earth, quite like the loess of China, is laid broadly as a surface deposit over the Mississippi valley from eastern Nebraska to Ohio outside the boundaries of the Iowan and the Wisconsin drift.
The loess soil, chiefly a mixture of porous clay and carbonate of lime, forms the bluffs bordering the bottom lands of the Missouri and is common in the N.
The soil is of four kinds: till or drift, alluvial, loess or bluff and geest.
It is built up of Tertiary deposits, belonging to the Sarmatian division of the Miocene period and covered with loess and black earth, and its escarpments represent the old shore-line of the Caspian.
The entire reforestation of its watershed to prevent the washing off of loess is another half of the work in the prevention of flood.
PART III The Housing Industry Among the four hundred millions in China the poor still live in huts and hovels, and in caves in the loess region of north China while the middle and the rich classes live in temples.
Loess was formerly regarded as simply a deposit of glacial or fluvial origin, but Richthofen's theory that its subsequent distribution was largely due to wind-transport (cf.
North of Maimana they form low undulating loess hills, in which most of the Band-i-Turkestan drainage is lost.
Those areas which are occupied by soil materials which have been brought into their position by the action of the wind may, as regards their character, be divided into two very distinct groups--the dunes and loess deposits.
Wherever the rainfall is considerable these loess deposits have proved to have a high agricultural value.
The human skeleton from the undisturbed loess of the Rhine, near Lahr, was found in nearly a horizontal position, but in such a manner as to forbid the idea of sepulchre.
In the alluvial plain into which the Schutter flows the the loess is two hundred feet thick.
In 1823, Aime Boue disinterred portions of a human skeleton from ancient undisturbed loess near Lahr, a small village nearly opposite Strasbourg.
Boue considers that the loessof the Lahr is continuous with that of the Rhine, and before the loess had been denuded there was not less than eighty feet of loamy deposit above the human skeleton.
The fragment of the skull from the loess of the Rhine (Alsace), by its depressed forehead and strongly projecting superciliary arches, greatly resembles the Neanderthal skull.
The human bones found in the loess of the Rhine, near Colmar, were two fossilized fragments of the skull.
The upper twenty feet consisted of loess and the lower forty feet of stratified gravel.
At this time some excavations were being made in the loess in Rock Island, when some rains fell in the late fall.
The rains had washed the loess extensively, and I found a number of places where it lay redistributed, with a fairly smooth surface.
The loess also, that singular deposit which wraps like a mantle so much of the undulating ground in Northern Germany, evidently engaged his attention, and we find the fruits of these studies in a later work.
It is a great fine stream and its shores, while mostly still low on the left, on the right rise here and there into moderate loess bluffs, far beyond which are seen higher elevations and bluish forested mountains.
So compact is the loess that there is no danger of a cave-in.
It does not therefore strengthen Professor Nehring's view that Europe during the deposition of the loess had a climate comparable to that of the Siberian steppes.
Sand and loess (a fine earthy deposit) had accumulated above it to a thickness of seventy feet.
Dr Steinmann regards the middle and lower subdivisions as equivalents of the 'older' loess of European Pleistocene deposits.
The upper subdivision is designated the yellow loess in contrast to the brown loess forming the middle layer.
A Mousterian type of implement is recorded by Commont from the later (younger) loess of the third terrace at S.
The loess and its divisions are not indicated in this Table.
Beyond these, the skeleton from the loess of Baradero presents no distinctive features save the remarkable length of the upper limbs.
In effect, the type of Solutre is assigned to the newer (juengerer) loess deposits.
It is very difficult to build roads in the loess of northern China; and the war-chariots that required roads had only just been introduced.
The Neolithic age In the period that now followed, northern China must have gradually become arid, and the formation of loess seems to have steadily advanced.
A wagon road up the point, from the river bottom to the hilltop, shows undisturbed loess the entire distance.
They were washed in when the loess was deposited, as claimed by the discoverers and by some of the Nebraska geologists.
All of them are made of the same earth as that which lies around them--a light, sandy loess which is easily removed with a shovel, requiring no picking or other loosening.
The hills and valleys were as they now exist; the erosion has been very slight as compared with what has taken place since the loesswas brought above the water, to which it owes its origin.
In support of this theory, too, is the positive statement of Nebraska geologists who have had ample opportunity to become familiar with loess in all its phases; and they claim the deposit is the original and has not been disturbed.
The objection made to this theory is that the earth thrown out of the hole was unmixed, presenting throughout the appearance and consistency of loess as it occurs where exposed in ravines or on slopes in the vicinity.
It would not take many centuries for mounds upon these sharp, exposed ridges to be entirely washed away, in spite of the fact that the fine loessis almost impermeable.
Soils Fine, dark chernozem (black earth) soils, rich in loess and humus, occur over a considerable portion of the northern Danubian plateau.
Away from the river, approaching the mountains, there is a broader area that is basically similar, but the subsoils are more porous and have allowed the humus and loess to leach downward from the surface.
Only the canal system of the center, important both for the irrigation of the fertile but porous loess and for the transportation of crops, is still in repair.
I have already observed, that a large part of this crater has been filled up with loess (p.
The interstratification above alluded to, of loess with layers of pumice and volcanic ashes, has led to the opinion that both during and since its deposition some of the last volcanic eruptions of the Lower Eifel have taken place.
The loess has also overspread the high adjoining platform near the village of Plaidt above Andernach.
The first idea which has occurred to most geologists, after examining the loess between Mayence and Basle, is to imagine that a great lake once extended throughout the valley of the Rhine between those two places.
Such a lake may have sent off large branches up the course of the Main, Neckar, and other tributary valleys, in all of which large patches of loess are now seen.
Both the terrestrial and aquatic shells preserved in the loess are of most fragile and delicate structure, and yet they are almost invariably perfect and uninjured.
In all these features it presents a precise counterpart to the loess of the Mississippi.
When a thickness of many hundred feet of loess had been thrown down slowly by this operation, the whole region was once more upheaved gradually.
A] At Cannstadt, near Stuttgart, in a valley also belonging to the hydrographical basin of the Rhine, I have seen the loess pass downwards into beds of calcareous tuff and travertin.
No human { } remains or works { Loess of the Rhine, p.
