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Sociology

within groups that may be described as follows: First, descriptive sociology, including all the preliminary work of stating observed phenomena of society as a genetic process motived by specific interests struggling with one another, and accommodating themselves with one another, in the evolution of persons and associations; second, social psychology, in which the problems of chief interest at present fall into two groups, (a) the study of the mind of primitive races, (b), the study of mental processes in masses, from the mob to the nation, the phenomena of public opinion, the transfer of individual impulses to the mass, and the ascendency of the mass over individuals by purely psychic means; third, social ethics, or the formation of judgments of value by progressive appraisal of types of interests and combinations of interests, and the definition of social aims on the basis of these appraisals of value; fourth, social technology, or the constructive application of known social facts and forces to the amelioration of human conditions in the direction of those judgments of value which are sanctioned by positive social ethics. Social technology is not restricted to consideration of ways and means by which the strongest may help the weakest. It is equally concerned with all scientilically sanctioned methods of Co-operation between the responsible members of society for the promotion of general progress. In addition to these four divisions of sociology, a few scholars are devoted to the methodology of the whole subject, that is, to the logic of social theory in general.

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mantles are exported. Socorro was laid out in 1540, where formerly stood an Indian village. In 1681 it was destroyed, and later re-erected at its present location. A serious revolt occurred here in 1781, and in 1810 it declared independence from Spanish rule. This example was followed by the rest of New Granada. Pop. of dist. (about) 20,000.

Within the last decade three important societies have been formed to promote the study of Sociology: L'Institut International de Sociologie, with its office at Paris, the Sociological Society, of London, and the American Sociological Society. It would be bibliography of the subject without prejuding important ques

impossible

tions on

avoid

to propose a brief

at present divided. In order to presenting an individual an expression of the

which sociologists are

opinion as

consensus of sociologists, we cite

Socotra (anc. Dioscorides), isl. in Indian Ocean, 15 m. N.E. of Guardafui and forming a de

the bibliographies contained in the proceedings of the St. Louis

Congress

vol.

of

of Arts and Science;

PP. 884-888, and vol.

viii, Department of Social Science. Socorro, tn., and formerly cap. S. America, 150 m. N.N.E. of Santander prov., Colombia, Bogotá, on a branch of the Mag

dalena R.

len goods,Panama' hats, and It manufactures woolplaited weaving of mantles is an impor straw goods, and the industry. Straw hats and

tant

Socrates

to hold political office, he showed no less resolution in withstanding popular clamor against certain generals who were thought to have failed in their duty, and during the régime of the "Thirty Tyrants' he risked his life by refusing to obey an order of theirs of which he disapproved. But he devoted himself chiefly to problems of life and conduct. Deeply conscious as he was of the need and the lack of clear insight into principles in matters of conduct,

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more and more clearly the utter inability of the examinee to give any coherent account of the moral notions he professed to know all about. Now, for those who were able to appreciate the positive aim that underlay the apparently destructive criticism of Socrates, such inquiry was stimulating in the highest degree, and it had this effect upon his disciples. But staid citizens, who had no intellectual cravings, strongly resented a method which entrapped them into a situation much more entertaining to the bystanders than flattering to their sense of their own importance. Young men, on the other hand, who had cleverness, without the more solid qualities of mind and character, were apt to be more dazzled by the destructive criticism than awakened to its positive significance. Hence we can partly understand how it was that, after many years of such activity, Socrates came to be looked upon by a large section of the Athenians as a disintegrating force in the public life of the city. Eventually he was formally accused of impiety and religious innovation, and of corrupting the youth of the city. What purports to be his defence is given in Plato's Apology; but he was condemned to death. The sentence was carried out by his drinking hemlock. In personal appearance Socrates was notoriously ugly, and in the Platonic dialogues he is represented as making jesting references to his snub nose and protruding eyes. For the outward incidents of life he cared little. In his inward life he had at critical junctures a consciousness of divine guidance or inspiration, which has been somewhat of a puzzle to modern psychological criticism. The name of his wife, Xantippe, is proverbial for alleged shrewishness.

To his contemporaries who condemned him to death, Socrates probably appeared only to be a sophist of a dangerous type. His disciples saw then, as we see now, that he was marked out from that class of popular teachers by his total freedom from self-seeking, and by his intellectual thoroughness. The peculiarity of his philosophical method lay, according to Aristotle, in his inductive procedure, and in his search for general definitions-e.g. of the virtues. But far more important than his method was the conviction in which it was rootedthat good and evil in action were the outcome of adequacy and inadequacy of knowledge. His famous doctrines, that virtue is knowledge,' and that no man willingly chooses what is evil,' are apt to seem strangely para

doxical to us. But this is due not so much to our truer views of morality as to our more superficial views of what constitutes real knowledge.

It was this conviction of the paramount importance of real knowledge for good practice that inspired Socrates's untiring search for moral truth. And it was just because his standard of real knowledge was so exacting that he seemed to his fellow-citizens to be the critic and enemy of established institutions, when he was really trying to ascertain the durable basis on which they rested. Moreover, his insistence on the supremacy of knowledge was certainly opposed in politics to the democratic notion of the equal fitness of all citizens for public authority and rule. For instance, it naturally enough seemed to Socrates the height of absurdity to appoint men by lot, as was the practice at Athens, to offices which demanded the rarest qualifications. Such opinions, however, did not commend him to the democracy, and political dislike probably had a good deal to do with his condemnation.

It was left for his disciples to attempt to fill out the ideal of ethical knowledge which Socrates conceived. But a type apparently alien to the whole spirit of his work was exhibited by the Cyrenaic school, founded by his pupil Aristippus of Cyrene, which identified the Socratic good with pleasure. And yet Socrates had been wont to maintain that the good life must needs be the happy life, and the Cyrenaics only turned this maxim the other way round. Another pupil, Antisthenes, the founder of the cynic school, went to the other extreme, and did his best to empty the Socratic knowledge of all content whatever. The true disciple of Socrates is, however, Plato. But Plato was, of course, more than Socratic; for he went far beyond the range of his master's thought, and passed from the simple ethical inquiries of Socrates into the profoundest problems of metaphysical speculation.

Socrates was not a writer, and what we know of his teaching is derived from the representations of his pupils, Xenophon (in his Memorabilia) and Plato (in his Dialogues, in the majority of which Socrates is the chief interlocutor). The relation of these two divergent representations to their original has been a problem for historical criticism. See Zeller's Socrates and the Socratic Schools (ed. 1885), and J. T. Forbes's Socrates (1905).

Socrates (c. 400), church historian, was born at Constantinople. He was the author of a

history of the church from 306 to 439 A.D., mainly an uncritical réchauffé of other writers. Editions by Hussey (1853); Bright, with introduction (1878); trans. in Bohn's Eccl. Library (1851); also in Schaff's Nicene and PostNicene Fathers (1891).

Soda, strictly speaking, is the base corresponding to the metal sodium, but used without prefix it generally implies anhydrous sodium carbonate, Na2CO3. This salt, known also as 'scda ash,' is obtained by evaporating the solution and igniting the residue. Washing soda, soda crystals, or sal-soda, is the decahydrated carbonate, Na2CO310H2O, obtained by allowing a hot solution of sodium carbonate to cool in water. Baking soda is the bicarbonate, NaHCO32H2O; and caustic soda is the hydroxide, NaOH, obtained by boiling the carbonate solution with slaked lime, filtering off the precipitated calcium carbonate, and evaporating the remaining solution. See SODIUM and ALKALI.

Soda Water. See AERATED WATERS.

Sodalite is one of the rockforming feldspathoids-a soda aluminum silicate with some chlorine. It is an isometric mineral, colorless or bluish, and occurs as an essential constituent in certain trachytes and syenites. It is closely related to Hauynite, Noselite, and Lozurite, which form together the Sodalite group.

Söderhamn, tn., Gefleborg co., Sweden, 44 m. N. of Gefle; has iron foundry and machinery factory, and exports timber and iron. The harbor, Stugsund, is 2 m. to the S.E. Pop. (1900) 11,258.

Sodium, Na, 23.05, an element of the alkali metal family which, though never occurring free in nature, is widely distributed in combination, chiefly as common salt or sodium chloride, NaCl. Common salt is collected from sea-water. In some cases portions of the sea are cut off and the water evaporated, leaving deposits of rock salt. Important deposits of this kind are found in Cheshire, near Middlesborough, in Austrian Galicia, Stassfurth in Prussia, and other places. Less important sources of sodium are the sodium nitrate deposits of S. America, of trona or sodium carbonate in Egypt, and sodium borate in California. The element also occurs in mar minerals, all animals, and to a less extent in plants. Sodium was formerly prepared by heating sodium carbonate and carbon to whiteness, the metal distilling off; but owing to the high tem perature required the process was very troublesome. It was superseded by Castner's method of heating sodium hydroxide with an

Sodium

In

intimate mixture of finely divided iron and carbon; and later by the Castner electrolytic process, which in a measure is a revival of the original process by which Davy isolated the element. the Castner electrolytic process, the sodium hydroxide is electrolyzed, 2NaOH=2Na+O2 + H2, an open iron cylinder is made the anode of the dynamo supplying the current, and surrounds the cathode, which consists of an iron rod, both being immersed centrally in molten sodium hydroxide. The sodium set free is collected in a cap over the cathode, in which it is protected from oxidation by the hydrogen simultaneously evolved. Sodium is a silver white, very soft metal, which is lighter than water (sp; gr. 0.98); it melts at 97° c. and boils at 742° c., forming a blueviolet gas. It is at once tarnished

by moist air, and must be kept in air-tight tins or, if in small quantities, under petroleum. Heated in air it burns with a dull glow, forming mainly the peroxide; when put upon water, it runs about as a silvery globule, rapidly displacing hydrogen and forming sodium hydroxide, 2Na+ 2H2O = 2NaOH+H2. The hydrogen does not catch fire unless the water is warm or the sodium kept still on a limited quantity, when it burns with the characteristic yellow flame, marked by a double yellow line in the spectrum, by which all sodium compounds can be recognized. Sodium, formerly much

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retained and the solution of ammonium chloride passes on. The crystals are dried and heated, by which they are converted into sodium carbonate, 2NaHCO3= Na2CO3 + H2O + CO2. The ammonium chloride is heated with lime, re-forming ammonia to be used again, 2NH4Cl = CaO = CaCl2+2NH3 + H2O; while the carbon dioxide from the lime kilns provides the necessary carbon dioxide for the main reaction of the process. The principal defect of the method is the waste of the chlorine of the salt, which becomes locked up in the almost useless calcium chloride.

'roaster' furnaces, and takes place in two stages-sodium bisulphate, NaHSO4, being primarily formed, NaCl + H2SO4 = NaHSÓ1 + HCl, and then at a higher temperature converted by the rest of the salt into the normal sulphate, NaHSO + NaCl = Na2SO4 + HCl, called 'salt cake.' Originally the hydrogen chloride was allowed to escape, and became a very serious nuisance, but the gas is now collected by passing it up tall 'scrubbers' or towers filled with coke or brushwood, down which a spray of water trickles and dissolves the gas, forming hydrochloric acid of considerable value. In the next stage of the process the sodium sulphate or 'salt cake' is strongly heated with small coal and limestone in a reverberatory furnace, in which, as a rule, the cylindrical hearth is made to revolve axially, and thus exposes the mixture thoroughly to the flames. A number of reactions take place, the chief of which may be roughly summarized as occurring in two stages vis. a reduction of the sodium sulphate by the carbon of the coal, Na2SO4 + 4C = Na2S + 4CO, followed by the interaction of the sodium sulphide formed with the limestone, yielding sodium carbonate, Na2S + CaCO3 = CaS + Na2CO3. The product, or 'black ash,' is then lixiviated with water to extract the sodium carbonate, leaving behind the calcium sulphide, together with insoluble impurities, as 'alkali waste.' The solution of sodium carbonate, containing a considerable proportion of caustic soda, produced by the action of quicklime formed in the furnace, is boiled down by the waste heat of the furnace. The crystals of Na2CO3H2O that separate are heated in a kiln to convert them into anhydrous 'soda ash,' or Na2CO3; and the red liquors' remaining are either worked up for caustic soda or carbonated by furnace gases.

used as a reducing agent to prepare metals like aluminium and magnesium, is still used in the reduction of organic compounds. It is also used in the preparation of sodium peroxide and cyanide, in gold extraction to keep the surface of the mercury used for amalgamation clean and active, and in the preparation of certain coal-tar products.

Of the compounds of sodium the carartificially prepared bonate Na2CO3 is by far the

most important, and its manu1s one of the leading industries.

facture British

The alkali

industry,' of which the main busithe preparation of this was first started about

ness

is

substance,

the year 1825 by James Muspratt, who adopted a process invented by Leblanc, and known both as Leblanc process' and the

the

'black-ash

trations of apparatus used in this and in other processes, see under

process.' For illus

ALKALI.

tion the

In all the processes of preparaably common salt, which in this starting-point is invaricase is mixed with sufficient sulphuric acid to convert it into

sodium sulphate. The reaction
is carried
out by heating the
in reverberatory

mixture

VOL. XI.-19

or

=

The ammonia-soda process may in its turn be superseded by more direct electrolytic methods, in which salt, either in solution or fused, is decomposed by an electric current, 2NaCl=2Na+ Cl2, and the resulting sodium converted, usually simultaneously, into caustic soda by water, 2Na+ 2H2O= 2NaOH+H2, or into sodium carbonate by water and carbon dioxide, 2Na + H2O + CO2 = Na2 CO3 + H2. Of the electrolytic processes there are two main types(1) Castner-Kellner, Rhodin, and Hargreaves-Bird, in which a solution of salt is electrolyzed in a cell divided by a porous diaphragm to separate the products formed (in this class also is the Aussig

The Leblanc process has been largely superseded by the Solvay or ammonia-soda' process. In the Solvay process water is first saturated with common salt and then with ammonia; the resulting ammoniacal brine is filtered, cooled, and pumped into tall iron cylinders, divided into a number of compartments by perforated horizontal shelves. Up this tower a stream of carbon dioxide is forced, bubbling through the liquid in numerous streams through the holes in the shelves, with the result that it is absorbed, and sodium hydrogen carbonate formed, NaCÍ + NH3 + H2O + CO2 NaHCO3 + NH,Cl. The sodium hydrogen carbonate separates in fine crystals, so that, when the resulting sludge is drawn off through filters, the crystals are

Bell' process in which the separation of the products is accomplished by gravity instead of a diaphragm); and (2) those in which the sodium set free is collected in a metallic solvent, such as mercury for a solution of salt, or molten lead (Acker process) if fused salt is employed, this being subsequently removed as caustic soda by the action of steam. The advantage of these processes is that valuable chlorine gas is obtained simultaneously.

Sodium carbonate, when anhydrous, is a white opaque solid, soluble in water, forming an alkaline solution, which when boiled down deposits a salt of the formula Na2CO3H2O. If, on the other hand, the hot saturated solution is allowed to cool, 'soda crystals,' or washing soda, Naz COз10H2O, separates in large translucent monoclinic prisms. When acted on by carbon dioxide the acid salt, sodium bicarbonate, NaHCO3, is obtained; this is similar to the carbonate, into which it is readily converted again on heating. Sodium carbonate is employed in the scouring of textiles, in the preparation of soap and glass, and in general in most cases where a soluble alkali is required. Sodium bicarbonate is used in medicine as an antacid, and, on account of the large amount of carbon dioxide that is readily set free from it by acids or by heating, it is an

important component of Seidlit powders and other effervescing mixtures, and of baking powder.

Sodium hydroxide, or caustic soda, NaOH, is also largely prepared by boiling sodium carbonate solution with milk of lime, Na2CO3 + Ca (OH)2 = CaCO3 + 2NaOH. When the reaction is complete, the insoluble calcium carbonate is allowed to settle, and the clear solution is boiled down until it solidifies on cooling, when it is cast in sticks or drums. The product obtained is a white solid, that fuses below a red heat, and readily dissolves in water, with considerable evolution of heat, to a syrupy liquid with intensely alkaline and caustic properties. It is chiefly used in the manufacture of soap, for scouring, and as a caustic alkali.

Sodium peroxide, Na2O2, is prepared by heating the metal in air in aluminium vessels. It is a yellow powder that acts as a powerful oxidizing agent; and as it is decomposed by water and acids, with the formation of hydrogen peroxide, Na2O2 + 2HCI = 2NaCl + 2H2O2, it is largely employed for bleaching purposes.

Sodium chloride, or common salt, NaCl, is the principal natural compound of sodium, and the source of sodium, chlorine, and their derivatives. See SALT.

Sodium nitrate, or Chile saltpetre, NaNO3, occurs in large quantities as 'caliche' in certain rainless districts in S. America, and is purified by crystallization. It forms rhombohedral crystals closely approximating to cubes, is very soluble in water, and is largely employed as a fertilizer, and for the preparation of nitric acid and sodium nitrite.

Sodium sulphate is prepared by the Leblanc process, and is a crystalline solid that separates from solution, combined with ten molecules of water, as Glauber's salt, Na2SO410H2O. It effloresces in air, is used in the manufacture of glass, and as an adulterant of washing soda. In medicine it acts as a valuable purgative, being very useful in the treatment of constipation and gout.

Sodium sulphite, Na2SO37H2O, is obtained by the action of sulphur dioxide on sodium carbonate, and forms large crystals that effloresce, owing to the formation of sodium sulphate by oxidation. It is largely used as a preservative for photographic developers.

Sodium thiosulphate, or hyposulphite (hypo'), Na2S2O35H2O, is another sodium compound largely used in photography and in leaching some varieties of silver

ore.

It is prepared by heating sulphur with sodium sulphite solution, and crystallizes in monoclinic crystals that are very soluble in water, in which they dissolve with

In

considerable reduction of temperature. It is employed in photography for 'fixing'-i.e for removing the silver halides unacted on that are left in the plate, film, or paper after the image is sufficiently developed. This action depends on the formation of a soluble double thiosulphate with the silver-e.g. Na2S2O3 + AgCl NaAgS2O3 + NaCl. treating silver ores, the silver compound is converted into a soluble thiosulphate of silver and sodium, which is removed by washing with water, the silver being ultimately precipitated and refined. Sodium thiosulphate is also used as an 'antichlor' to remove chlorine that may have been left after bleaching fabrics such as paper by its aid. For other compounds of sodium, see BORAX and SOLUBLE GLASS, and the acids of which they are salts; also Lunge's Sulphuric Acid and Alkali Manufacture (1902). See also under ALKALI.

Sodium Chloride. See SALT, COMMON.

Sodom. See APPLE OF SODOM. Sodoma, IL (1477-1549), the cognomen of Gianantonio Bazzi, sometimes erroneously written Razzi, was born in Piedmont. In 1497 he went to Milan, and became a follower of Leonardo da Vinci; four years later he settled in Siena. His finest early works are the twenty-six frescoes of the life of St. Benedict at Monte Oliveto. In 1507 he painted a ceiling in the Vatican. The Madonna and Saints, in the National Gallery, painted about this time, shows Leonardesque influence. Siena possesses his masterpieces, the frescoes in the Chapel of St. Catherine in San Domenico (1526). A poetical painter, with creative mind and glowing feelings, he at times rivals Leonardo in the grace of his women. fish and vicious, he cared little for his own reputation or that of his art, though doubtless Vasari gives an exaggerated account of his profligate life, and undervalues him as an artist. See Life, by Albert Jansen (1870) and R. H. H. Cust (1906).

Sel

Sodom and Gomorrah, two of the cities of the plain' destroyed by fire from heaven for their heinous immorality (Gen. 19: 24); located by some authorities to the north of the Dead Sea and by others to the south. There is no Biblical support for the idea that the cities stood upon the site now occupied by the lake and are submerged in its waters. Stories of the destruction of cities and peoples for their wickedness are common, and are generally regarded as unhistoric.

Sodor and Man. See MAN.
Soest, tn., Prussia, prov. West-

phalia, 28 m. by rail E. of Dortmund; manufactures machinery, hats, cigars, and beer. In the middle ages it was one of the most important members of the Hanseatic League. Sir Peter Lely, the painter, was born here in 1618. Pop. (1900) 16,721.

Sofala, a former native state on S.E. coast of Africa, from mouth of Zambezi to Delagoa Bay; now part of Portuguese E. Africa. The seaport, Sofala, has been superseded by Beira.

Soffit, or INTRADOS, the under surface of an arch ring or similar structure. See ARCH.

Sofla (Bulg. Sredets), tn., cap. of Bulgaria, in a fine plain at N. foot of Rhodope Mts. It has been largely rebuilt within the last twenty years, the streets converging upon the palace. Exports hides, maize, linen, cloth, and silk. It is the seat of a Greek Orthodox metropolitan and of a university, and has hot mineral springs. Its name in Roman times was Serdica. There, in 343 A.D., a famous church council was held; it fell into the hands of the Turks in 1382; the Russians occupied it in 1878. Pop. (1900) 67,920.

Soft Grass, a genus (Holcus) of hardy grasses, with loose panicles of two-flowered spikelets. The species are of easy cultivation in ordinary garden soil.

Sogdiana, anciently a region of Central Asia, bounded by the Oxus on the s. and the Jaxartes (Syr Daria) on the N.; westwards it extended nearly to the Caspian Sea, and eastwards to the land of the Sace and Seres. It comprised the kingdom of Bokhara, still called Sogd, and was conquered by Alexander in 330

B.C.

Sogne Fjord, an indentation on w. coast of Norway, 136 m. long, terminating in the Lyster Fjord, 2 to 4 m. broad, and over 4,000 ft. deep, everywhere surrounded by steep rocky walls. It has numerous winding branches-Aurland Fjord and Närö Fjord to the s., and Sogndal Fjord and Fjärland Fjord to the N., the latter penetrating to the glaciers of Jostedalsbrä.

Sohar (anc. Masun), fort. seapt., Oman, S.E. Arabia, on Gulf of Oman, 120 m. w.N.W. of Muscat. Pop. about 5,000.

Soignies, tn., Hainault prov., Belgium, 22 m. by rail S.W. Brussels; has an old abbey church, and flax-spinning and bleaching. Pop. (1901) 10,124.

Soils are the loose materials resulting from the decay (physical and chemical decomposition) of rocks, into which the roots of plants penetrate and from which they derive the supplies both of moisture and plant-food needed

Soils

for their growth. As a rule, soils contain also the remnants from the decay of vegetable and animal matter grown in and upon them, called vegetable mould or humus. All good agricultural soils should contain from one-half to three or more per cent. of humus. The rest consists of sand and powdery matter of various degrees of fineness, together with a certain amount of clay, varying from one to as much as fifty per cent. of the whole. According to the proportions of these ingredients, soils are classified by farmers as light or heavy: referring not to the actual

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greatly hastens and facilitates the chemical effects.

Physical Disintegration.Changes of temperature alone produce striking results upon rocks consisting of several minerals, as they mostly are. Heat expands, cold contracts, these minerals differently and in different directions. Thus minute crevices are formed, which are gradually widened by wetting and freezing, as well as by the fallingin of dust; so that finally the surface layer crumbles off, leaving the same process to be repeated indefinitely. On level plateaus or

Soils

usually show shades of gradual transition. Colluvial or hillside upland soils usually contain both angular and partly rounded fragments of the several kinds of rocks occurring on the hillsides. Alluvial soils, whose materials are usually derived from extensive drainage areas with many kinds of rocks, contain mostly or altogether rock fragments rounded by rolling and mutual grinding and polishing while being carried; that is, cobble, shingle or pebbles, gravel, and sand. During their progress down-stream these also scour and abrade the bed and banks of the

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weights of the soils, but to the facility in working them. Broadly speaking, light soils are those containing much sand, or humus, or both; while heavy soils are those containing much clay. Intermediate between sandy and clayey soils are mixtures of the two called loams, which are generally preferred for culture purposes.

The decay or weathering' of rocks by which soils are formed is brought about by two kinds of agencies, physical (or mechanical) and chemical. The former are usually first in order of time, and bring about the more or less fine pulverization of rocks; which then

(Photo by Fradelle & Young.) gently sloping lands the débris may remain where formed, and so produce soils in place' or sedentary soils. On more sloping surfaces rains and gravity will move them down the slopes, forming hillside uplands or colluvial lands; and finally they may be washed into the streams, to be deposited in the valleys and form alluvial soils. The latter are generally the most productive, as they consist of the finest particles formed in weathering.

Sedentary soils contain only angular fragments of the original underlying rock from which they were formed, and into which they

streams, thus adding still farther to the load of sediment carried and finally deposited. The latter is thus naturally of quite a generalized composition. (See Fig. 3.)

Glacier Action.-While the flowing water of hillside rills and streams is at present most active in pulverizing rocks, in the past flowing ice has produced prodigious effects by its grinding power when charged with rocks, as it always is where glaciers descend from high mountains. Glaciers have been much more extended in former times than now, and wherever a stream originates in a glacier we find it

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