Hydrothermal alteration products of serpentinite near Takovo, Yugoslavia, were studied by X-ray powder diffraction and chemical analysis. A zone of mainly blue clays adjacent to the hydrothermal vein contains intimately associated chromium kaolinite and tosudite at higher hypsometric levels and chromium halloysite(10Å) form at lower levels. A second zone of green clays contains principally illite/smectites, with predominantly illite layers nearer the first zone and smectite layers at greater distances. The potassium content diminishes as the proportion of illite layers diminishes. The composition of the smectite layers in the illite/smectite with the least proportion of illite is shown to be beidellitic. The mineralogical and chemical changes across the zone of alteration are interpreted in terms of two stages of alteration in which the second is more acidic than the first and is responsible for the inner zone of chromium-bearing kaolinite and tosudite and chromium halloysite.

A number of otherwise poorly understood compositional-structural relationships in mixed-layer illite/montmorillonites appear to be explained by ordered interlayering of 2:1 units. The ordering appears to be between high and low charge 2:1 units. The relationship between per cent expandable layers and mean lattice charge in natural materials shows a scatter that is nicely bracketed by hypothetical curves constructed assuming random or completely ordered interlayering for several types of 2:1 charge distribution. Natural samples with 30–50% expandable layers plotting near the “ordered” curves have diffraction peaks at 25 Å for two water layers in the expandable layers and 27 Å with two glycol layers; samples plotting near the “random” curves do not have these peaks and have poorly developed 001/001 reflections.

Some tentative conclusions are: (1) illites are virtually non-expandable at lattice charges significantly less than that of ideal mica because of ordering of high-low charge 2:1 units, (2) illites and mixed-layer illite/montmorillonites with the same mean lattice charge show a range of expandability because of varying degrees of ordering, (3) the highly variable CEC of samples with the same expandability also results from a varying degree of ordering.

An interesting petrological implication results when it is realized that a sample with a given bulk composition can have a wide range of expandability, depending on ordering. Low expandability, achieved by ordering, should be promoted by formation at high pressures. Glauconites, known to form largely at the time of sedimentation, appear to be dominantly randomly interstratified; illites and illite/montmorillonites, which may form on deep burial of argillaceous sediments, are dominantly ordered.

We still cannot speak of a Bantu philosophy today—or, more generally, of a Negro-African philosophy—without referring first of all to a pioneer work: La philosophie Bantou, by R. P. Tempels, which in 1948 created for the first time an orthodoxy in this hitherto unexplored, or nearly unexplored, field. The fact that this orthodoxy has become accepted would certainly not be enough to justify a heresy. But there may, however, be good reasons to reject it.

In its time R. P. Tempels' work was well received, on the whole with sympathy by the Europeans whom it endeavored to reach, and with unreserved enthusiasm by the intellectuals of Central and West Africa, for whom it opened a way back to their native roots. Quite apart at the moment from any question of philosophy, the author interpreted something essentially and inherently African.

Experimental solubility data for gibbsite and kaolinite are reviewed and applied to the problem of gibbsite stability within the natural environment. It is concluded that free alumina compounds formed (only) in lateritic soils will tend to silicify spontaneously in all sedimentary environments. This metasomatic reaction should be accompanied by massive volume expansion: unusual textures are to be anticipated.

Petrographic and field descriptions of a number of ancient kaolinitic sediments (some with, some without free alumina) are reviewed. It is concluded that silicification of hydrated aluminum oxides was an important mechanism of kaolinite formation in ancient sediments and that free alumina compounds persist only as a result of the unusual volume expansion associated with kaolinite formation.

In the absence of oxygen, Fe(II) chloride, sulfate, and carbonate solutions react at pH 6.5 to 7 with aluminum hydroxide suspensions to form new Fe(II)-Al(III) hydroxy anion compounds of the pyroaurite group. The Fe(II)-Al(III) hydroxy-chloride and -sulfate compounds are isostructural with Fe(II)- Fe(III) “green rust” compounds with A1 essentially substituting for Fe(III). Where CO32- is the only anion in the system, an Fe(II)-Al(III) compound isostructural with hydrotalcite is formed. Either in the dried or wet state, these compounds are unstable in air due to oxidation of Fe(II). Oxidation of the dried sample in air yields akaganeite or aluminous ferrihydrite, whereas, if the sample is maintained in a moist condition and oxidized by air under water, lepidocrocite or aluminous goethite is produced along with small amounts of ferrihydrite. On X-ray powder diffraction, the lepidocrocite so formed commonly shows no diagnostic (020) basal reflection, or one with a markedly reduced intensity. The products of oxidation, and the rapidity of their formation, appear to be dependent on the composition of the initial double hydroxy compound and the conditions under which the oxidation is carried out.

The green colored compounds commonly observed in gleyed soils also rapidly become yellow brown on exposure to air, and difficulty arises in the identification of the Fe oxide phases assumed to be present. Similar conditions and reactants to those involved in the formation of the compounds described above are expected in these soils, and it is suggested that Fe(II)-Al(III) members of the pyroaurite group may form in such an environment.

The layer structure of kaolinite from Twiggs, Georgia and fire-clay type kaolinite (Frantex B, from France), particle size separates 2–0·2 μm was studied by high resolution electron microscopy after embedment in Spurr low-viscosity Epoxy media and thin sectioning normal to the (001) planes by an ultramicrotome. Images of the (001) planes (viewed edge-on) of both kaolinites were spaced at 7 Å and generally aligned in parallel, with occasional bending into more widely spaced images of about 10 Å interval. Some of the 10 Å images converged to 7 Å at one or both ends, forming ellipse-shaped islands 80 to 130 Å thick and 300 to 500 Å long. The island areas and interleaved 10 Å layers between 7 Å layers may represent a residue of incomplete weathering of mica to kaolinite.

The proportions of micaccous occlusions were too small and the layer sequences too irregular to be detected by X-ray diffraction. The lateral continuity of the layers through the 7-10-7 Å sequence in a kaolinite particle would partially interrupt or prevent expansion in dimethyl sulfoxide (DMSO) and other kaolinite intercalating media. Discrete mica particles were also observed with parallel images at 10 Å, as impurities in both kaolinites. The small K content of the chemical analyses of the kaolinite samples is accounted for as interlayer K, not only in discrete mica particles but also in the micaceous occlusions.

The cation-exchange capacities (CEC) of a previously well-characterized beidellite have been estimated nondestructively from X-ray photoelectron spectroscopy (XPS) data following exchange by various cations. The CEC obtained as an atomic ratio to silicon from Na- and Ca-clays are close to that derived chemically, i.e., 0.10(2), and 0.10(1), respectively, compared with 0.12(1). However, the apparent CEC obtained following K-, Pb-, and Ba-exchange are all about 50% greater. These measurements are complemented by XPS studies of clay exchanged in a solution containing both Ca and Ba ions where XPS gave a total apparent exchange capacity relative to Si of 0.16, with 0.10 from Ca and 0.06 from Ba. Bulk chemical analysis has, however, shown that the true Ba value is only 0.01. It is concluded that the cation excess detected by XPS—a technique with a total sampling depth of only about 100 Å—is concentrated at the surfaces of the clay particles.

In the last fifteen years, biology has made such considerable progress that it arouses the highest hopes. But despite the importance of the discoveries, particularly in the field of molecular genetics, one must admit that much still remains to be done if life is to be appreciated as a whole, including superior organisms. However, research is facing the complexity of the problem with ever-increasing success, moving in a completely new direction, not simply on a cellular level, but on a molecular and atomic scale. It is this radical change in thinking methods that might perhaps enable the scientist of today to study hitherto out-of-the-way fields, albeit still from a highly speculative point of view, by giving him scope for new ways of thinking. This is particularly true of psychology which, it seems, has not as yet been the subject of reasoning on a molecular scale.

Flint clay is defined as a sedimentary, microcrystalline to crystalline clay (rock) composed dominantly of kaolin, which breaks with a pronounced conchoidal fracture and resists slaking in water. Additional ceramic (refractory) properties are implied, but not expressed, in the definition. Flint clay first given recognition in the U.S.A., has been observed on all continents; it will probably be found to be more abundant than its occurrences reported to date. It occurs in rocks mainly Carboniferous or Cretaceous in age, and is invariably associated with plant- or coal-bearing measures.

The environment of deposition is commonly lowlying paludal, in basins in either clastic silicate rocks or in karstic carbonates. It is inferred that parent illitic and/or kaolinitic clay colloids were transported into the swamps and there under-went further dialysis, alteration, and eventual crystallization in situ, producing a notably homogeneous kaolinite clay possessing interlocking crystallinity. Some occurrences were further desilicated to high-alumina minerals, particularly to diaspore and boehmite.

Flint clay is interpreted as being an intermediate member of a so-called flint-clay facies which is a claystone sequence ranging from high-alumina minerals (or potentially so) formed on the highest part, structurally and/or topographically, of the depositional area, and grading down-structure and/or lower in elevation through flint clay to iliite-kaolinite plastic clay and thence to marine illitic shale, all being equivalent stratigraphically. The geochemical reactions are depotassification of parent clay by substitution of K+ by H+, and desilication, especially where high-alumina minerals are formed.

The relation between government and industry is a problem not of economics but of political economy. It is a problem of controlling and civilizing economic power in order that it may be used for the public good within the framework of democratic institutions. It is a problem of striking a delicate balance between individual freedom and centralized control. It is a problem for which there is no monistic solution and which transcends the clichés of popular controversy between conservatives and liberals.

Infrared spectroscopic, X-ray diffraction and gravimetric techniques were used so study the vapor phase adsorption of ethanol on homoionic Cu-, Al-, Ca,, Na-, and NH4-montmorillonite films. Equilibration of these films with ethanol vapor at a relative pressure of unity reduced the water content to less than 0.7% (300°C). As dehydration proceeded, the infrared absorption bands of the residual water were observed. Apparent differences between different cation saturations are reconciled by a consideration of the different types of ion-dipole interactions involved. Adsorption isotherms and X-ray diffraction results substantiated the interpretations of the infrared data. Prolonged evacuation did not remove all of the adsorbed ethanol as shown by spectroscopic and gravimetric techniques. Cu-, Al- and Ca-montmorillonite retained 4.5, 7.9, and 4.5 molecules per ion, respectively, while Na- and NH4-clays retained less than one molecule per cation. Ethanol loss occurred rapidly at 40% relative humidity except in the Cu-system where 70 hr were required for complete replacement. These differences indicate that the adsorption and retention of alcohol by montmorillonite is affected by the saturating cation and that alcohol and water compete for the same adsorption sites. Ion-dipole type interactions should thus be considered in adsorption mechanisms of alcohol on montmorillonite.

The absorption of biologically important purines, pyrimidines, and nucleosides by Li-, Na-, Mg-, and Ca-montmorillonite has been studied in aqueous solutions over a range of pH values 2–12. The initial organic concentrations were about 1 m.molar. The ratio clay to organic compounds was such that only up to 25 per cent of the exchange capacity could be saturated by organic cations, but, depending on conditions, up to 100 per cent of the available organic material was absorbed. Of the nineteen compounds studied, only thymine, uracil, and their nucleosides were not absorbed under the experimental conditions. Absorption occurs primarily as a cation exchange reaction under acid conditions and varies with the basicity of the compounds, their aromatic or non-aromatic character, and the possible extent of their van der Waals interaction with the silicate layers. Nucleosides generally are less strongly absorbed than their purines or pyrimidines because their non-planar structure permits less van der Waals interaction; their absorption is influenced by the differences in swelling behavior of montmorillonite with mono- and divalent cations.

Whoever knows a little about China—even very little—knows, in one way or another, about the Taoist Immortals, although our knowledge may be limited to the representation of them on a bit of sculptured jade, on a Han mirror or in some wood engraving. One has heard of them as an essential part of Chinese folklore. In the book of Taoist saints, the Liesien tchouan, they may be observed in all their oddness, living on pine cones or the “marrow of stones” and flying off into the air toward the apotheosis of some unknown paradise. This aspect of the Immortals has been studied often and well. But there is another aspect to the Immortals no less important, a philosophical aspect which, I believe, deserves our attention. Sun Yat-sen, the “Father of the Chinese Republic,” is certainly not given the name of “Hidden Immortal” (Yat-sen, Yi-sien) out of a simple interest in folklore, and the heroes of the Chinese novel, Kia Pao-yu of the first Hong-leou mong, dedicated themselves to achieve the way of the Immortals for reasons that went deeper and were more intelligent than mere superstitious emulation of some grotesqueries of occult folklore. No, the Chinese Immortal is a veritable hero of the same stamp as Saints of the Christian tradition and like the latter he embodies a religious philosophy of the highest inspiration.

The electron microscope has been used to study changes in particle size, shape, and arrangement that occur during the hydration of clay in soil—cement. Samples of kaolinite, of a mixture of silica flour and montmorillonite, and of a natural silty clay were mixed with sufficient portland cement to produce soft—cement. Specimens were cured at constant moisture content for periods up to 32 weeks after compaction at optimum moisture content for the mixture. At the end of the curing period surfaces of fresh fractures were replicated, and the replicas were studied using the electron microscope.

All three mixtures showed similar behavior. Initially the fabric is one of separate portland cement grains distributed throughout the clay soil. As hydration of the cement proceeds, cement hydrate gel forms along the edges of groups of clay particles. Reaction between the soil and the cement is observed early in the hydration period. As hydration continues the soil grains are more and more broken down and the cement gel diffuses more extensively throughout the mass. Eventually, the breakdown of the soil minerals and the formation of hydration products reaches a point whore the soil and cement can no longer be distinguished as separate phases.

Industrial societies are seeking a civilization for which they have not as yet found a firm framework of moral and social values, nor definite forms of social life. That is why traditional peasant values and ways of life, and social institutions in rural communities, still appeal so strongly to emotion and remain so strikingly evocative in our urbanized, industrialized world. Village society is still seen as an ideal—and often idealized—social model; industrial societies would like to have something comparable in their vast cities.