Anthropologists customarily use the term ‘tribe’ to designate two realms of different yet connected facts. On the one hand, nearly all of them make use of it to distinguish one type of society among many, one specific mode of social organization which they compare to others—’bands,’ ‘States,’ etc. There is, however, a lack of unanimity on this point, an outcome of the imprecision, the haziness of the criteria selected to define and to isolate these various types of society. But the discord is deeper yet with respect to the second use of the term ‘tribe,’ when it is used to designate a stage in the evolution of human society.

Previous investigations have demonstrated the influences of interlayer cation composition, relative humidity, temperature, and magnitude of interlayer surface charge on the interlayer hydration of montmorillonites and vermiculites. It has been suggested that the sites of layer charge deficiencies may also have an influence upon the amount of hydration that can take place in the interlayers of expandable clay minerals, if the interlayer cation-to-layer bonds are considered as ideally electrostatic, the magnitude of the forces resisting expansion may be expressed as a form of Coulomb’s law. If this effect is significant, expandable structures in which the charge-deficiency sites are predominantly in the tetrahedral sheet should have less pronounced swelling properties than should structures possessing charge deficiencies located primarily in the octahedral sheet.

Three samples that differed in location of layer charge sites were selected for study. An important selection criterion was a non-correlation between tetrahedral charge sites and high surface-charge density, and between octahedral charge sites and low surface-charge density.

The effects of differences in interlayer cation composition were eliminated by saturating portions of each sample with the same cations. Equilibrium (001) d values at controlled constant humidities were used as a measure of the relative degree of interlayer hydration.

Although no corrélation could be made between the degree of interlayer hydration and total surface-charge density, the investigation does not eliminate total surface-charge density as being significant to the swelling properties of three-sheet clay-mineral structures. The results do indicate a correlation between more intense expandability and predominance of charge deficiencies in the octahedral sheet. Conversely, less intense swelling behavior is associated with predominantly tetrahedral charge deficiencies.

A white clay from the Jatoba talc mine, Castro, Paraná, Brazil, is shown by chemical analysis, X-ray and electron diffraction, and by thermal analysis to be essentially pure antigorite in the strict sense of the term. Single crystal electron diffraction patterns give various values for the long a parameter, with 43·5 Å perhaps the most commonly occurring, b = 9·25 Å, d(001) = 7·25 Å. X-ray powder diffraction gives d(001) = 7·26 Å and b = 9·23 A. Electron micrographs show irregular platy and lath-like crystals of about 0·5–2 μ size with large development of (001) planes and with b in the direction of elongation. Other crystals are observed with very unusual forms, some having holes through them. They show mainly 0kl diffraction patterns and lie with the basal (001) planes normal to the stage of the instrument. The chemical analysis agrees closely with the ideal serpentine composition and the differential thermal analysis curve is consistent with antigorite.

The physical and chemical interactions between organic amines and mineral surfaces are of considerable importance in many industrial applications. For example, the preparation of organophilic minerals often involves the adsorption of organic amines, or the ion exchange of the minerals with quaternary ammonium salts (Jordon, 1951; Miller and Faust, 1972). Chemical interactions occurring in these systems have been studied because of their relevance to an understanding of the chemical nature of the clay surface. A number of these studies have reported on the decomposition of adsorbed amines and alkylammonium-mineral complexes at elevated temperatures, usually in excess of 100°C (Chaussidon and Calvet, 1965; Weiss and Roloff, 1963; Durand, Pellet and Fripiat, 1972; Chou and McAtee, 1969). It is now well established that under these conditions the mineral may have potential strong-acidity, and these reactions have been explained in terms of acid-induced decomposition or rearrangement of the adsorbed amines or their derivatives. However, there have been few studies of the reactions of organo-mineral complexes at temperatures below 100°C, under conditions where retention of adsorbed water could be expected to moderate the mineral surface acidity.

Dissolution data on five of the six illites reported by Reesman and Keller (1968) indicate that these illites are more stable than was previously thought. The revised Gibbs free energies of formation (ΔGf0) with respect to the ‘ideal’ illite formula and the muscovite formula are

Use of muscovite formula as an indirect comparator provides a means of predicting the relative stabilities of these chemically complex materials.

The response of illite-equilibrated solution to a kaolin ΔGf0 was found in all samples in which a 7 Å mineral phase was detected by X-ray diffraction. Stability diagrams based upon the ΔGf0 with respect to ideal muscovite and kaolin formulas show a rather wide range in chemical conditions through which illites and kaolin minerals with differing ΔGf0 would be stable. However, in carbonate rocks and sea water illite is stable relative to kaolin. During the weathering of carbonates the lower pH zones in the clay-rich residuum above the carbonates favor the transformation of illite to kaolin minerals.

Various dehydroxylated micas and rectorites were acid-treated. Rectorite-type mixed-layer mineral was formed from 2M1 and 2M2 mica and random mixed-layer mineral from 1M and 1Md mica. Rectorite was formed again from dehydroxylated rectorite. The rehydration and rehydroxylation properties of dehydroxylated rectorite and 2M sericites were found to be similar.

I term a group of texts “African philosophy”: to be precise, the group of texts written by Africans and defined as “philosophic” by the authors themselves.

This definition, let us note, involves no “petitio principii.” The sense of the adjective “philosophic” need not be reckoned with here, and even less the cogency of the adjective. All that matters is the fact of the adjective itself, the deliberate recourse to the word “philosophy” whatever, by the way, the sense or meaninglessness of the word may be. In other words, all that concerns us is the philosophic intention of the authors, not the extent (hard to evaluate) of its effective realisation.

Why did Einstein say of Dostoevski: “He gives me more than any other thinker, more even than Gauss?” What could Dostoevski give to the originator of the theory of relativity?

It is certain that it is not a question of the philosophical, moral or social ideas with which he filled the thoughts and utterances of his heroes. Einstein drew from artistic literature the driving force for his research and not the elements of a scientific concept of the world. The influence of artistic creation on scientific creation was the result not of any positive answers but of the common aesthetic ground in the problems and contradictions of the earlier representation of the world and in the intensity of the artistic conception of the infinite contradictions and complexities of the origin of the world.

The structure and hydration status of attapulgite clay after heating at elevated temperatures and the stability of parathion on these clays was studied. Using infrared spectroscopy and scanning electron microscopy it was found that the bound water was lost in two steps, at 250° and 450° with the first step being largely reversible. At 650°C the structure began to dissolve releasing significant amounts of Mg, and a decrease in aggregate porosity was noted. At 850°C an amorphous phase was formed bearing little resemblance to the original attapulgite. Parathion was stable on all of the preheated clays when kept at 25°C for 190 days. The reactions of parathion on the preheated clays was studied at 110°C Hydrolysis of parathion was found to be minimal. Isomerization was the main reaction occurring on the Ca-attapulgite, whereas on an organo-clay no isomerization was observed. A mechanism for the isomerization reaction is proposed which entails a distortion of the phosphate moiety of the pesticide by the oxygen of the ligand water resulting in the conformational changes necessary for the isomerization to take place. On the organo-clay such a conformation was not possible; hence no isomerization occurred.

The interest now being manifested in the history of African civilizations (an interest which one may be assured in advance can never be satisfied), raises the question whether the function which, in our societies devolves upon the diffusion of history, has not sometimes been fulfilled on the African continent by activities based on specific functions generally considered devoid of historical significance, as, for example, religion.

When, in the year 1516, Sir Thomas More wrote his book about the ideal state, he located it on the Island of Utopia, which was supposed to have been discovered by Raphael Hythlodaeus, a companion of Vespucci on his fourth voyage. At first a fictitious geographical name, the term “utopia” continues to live in the minds of men, although it no longer is relevant to geography or to voyages of discovery and is by no means necessarily connected with the description of ideal states. Today, according to dictionaries and encyclopedias, “utopian” describes any plan which seems impossible to realize; the word is weighted either with resigned regret or with the forbearance of the sensible soul who well knows that the ideal state would in the end prove no better than the existing one.

Until now, the analysis of dreams has dealt almost exclusively with their contents and has been concerned with an attempt to extract all their meaning from the images which appear in them. As is well known, the incorporation into science of the analysis of dreams began with Freud, who, upon discovering a basic hypothesis or subject, quickly arrived at a kind of metaphysics of which dreams are the manifestation: the libido, which is, in essence, desire.

But, in dealing with the phenomenon of dreams as a part of human life, one must first study their form: the form of the dream, first of all; later, the species of dreams, if such species exist. One must, that is, arrive at a phenomenology of the dream and of dreams. Such a phenomenology does not exhaust the study of dreams; it is simply a first approach to knowledge of dreams, an introduction.

This paper deals with the problem of value in the psychoanalytic theory of human nature and culture. In particular, it is concerned with this problem in the theory as it was expounded by Freud. First, I shall show how the problem of value is an integral part of the therapeutic situation which Freud encountered. In regard to Freud's own assessment of the problem, I shall point out some difficulties of a cognitive and a moral nature for which his theory must, but cannot, account. In the second part of the paper I shall show how the problem of value is an indispensable component of Freud's overall theory of man and culture, what may be called his “general theory.” This part will be concerned with its peculiar normative and scientific status. I shall try to show how descriptive and prescriptive ethics are (1) confused in Freud's theory and (2) that it is a confusion that cannot be avoided if the theory is to serve the purpose that Freud seemed to believe it must serve, namely, as a science not only of what man is but also of what man ought not to be.

A 1–0·2 μm fraction from a soil in the Dominican Republic was studied by X-ray diffraction combined with solvation, cation saturation, and heat treatments. I.R., thermal (DTA, TGA) and chemical analyses were also made. This soil is saline and alkaline and its mineral composition is greatly influenced by the lacustrine parent material and poor drainage.

In addition to swelling chlorite, illite, kaolinite, carbonates and quartz are present in the 1–0·2 μm fraction. The swelling chlorite expanded to over 18 Å when Mg saturated and solvated with glycerol or water. Lower spacings with other cations and ethylene glycol were observed. 1 N HCl treatment partially removed the interlayer hydroxides in the chlorite and 6 N HCl destroyed the mineral. The mineral gave a reflection close to 14 Å up through 600°C but collapsed at higher temperatures to 10·2 Å.