The results of X-ray diffraction, DTA, i.r. spectroscopy, and chemical tests are presented for some chlorites typical of the Flagstaff Hill area. The area is notable for the large variety of chlorite types occurring in considerable quantities. Chlorite, in this area, is found as veins, as pseudomorphs, and as individual crystals. Textures vary from massive, fine-grained aggregates to books which are more than 20 mm in width. Crystals more than 5 mm in size occur in parallel groupings at rock interfaces. Judging from 45 chlorite samples studied, sheridanite is most abundant; clinochlore and ripidolite are common. Penninite and its Cr-chlorite equivalent are less abundant. The parent rock is an irregularly shaped ultramafic body surrounded by low-grade schists and located very close to a granodiorite stock. The original ultramafic rocks have been highly altered by metamorphism and metosomatism into assemblages comprised mainly of serpentine, talc, hornblende, and chlorite with relics of olivine, pyroxene, and other less abundant original minerals. Much of the exposed rock is essentially monomineralic, mostly consisting of various polytypes of serpentine. Preliminary investigation indicates that the area merits much more study because of the opportunity for readily observing the various chlorite types and determining their genesis, alteration sequences and weathering characteristics. The area, being easily accessible, could also serve as an adequate source for samples to be used as reference standards.

The French School of the Far East has recently published under the above title an important study in comparative law, the conclusions of which go far beyond the juridical framework to which its tide and the author's background would appear to assign it. For this reason, it seemed necessary to call the work to the attention of readers of this journal, especially those who are interested in the problems of the relationships between the original indigenous infrastructure and the Indian and Chinese superstructures in South East Asia.

The clay minerals formed in a deeply weathered boulder conglomerate of Middle Old Red Sandstone (Devonian) age in north-east Scotland have been studied by a variety of physical and chemical techniques. The granite and granulite boulders in this deposit are completely weathered. With the exception of microcline, all the feldspars in these rocks—orthoclase feldspar, orthoclase-microperthite, albite, and oligoclase—weather to a Cheto-type montmorillonite, poor in iron. Electron and optical microscopy indicate that the weathering transformation is a direct one, without the intervention of any intermediate crystalline or well-defined amorphous phase. Structural control of the primary mineral over the formation of the montmorillonite seems to have been a minimal factor and the evidence suggests that the clay mineral crystallized from the soluble or colloidal products arising from the decomposed feldspars. Smaller amounts of kaolinite also formed during weathering but largely from the weathering of muscovite. The environment in which these changes occurred seems to have been alkaline in a relatively closed system. Chemical analyses of related cores and weathered shells of granite and granulite bounders show only a slight decrease of silica and an increase in magnesia. Judging from the extent of alteration to secondary clay minerals, the order of resistance towards weathering of the primary minerals in these rocks is plagioclase = orthoclase < muscovite < biotite < microcline < quartz.

Until the nineteenth century, history was largely a chronicle of the deeds and misdeeds of kings, nobles, and armies. In revolt against a general obliviousness to the daily life and affairs of ordinary people, democratic historians swung to the opposite extreme: so the part actually played by kings has, during the last half century, been grossly under-rated, even though most of the attributes of kingship are now exercized, on a larger scale than ever before, by the all-powerful sovereign state.

It is easy to guess from the title of this article that its content will deal with the current changes in the foundations of physical sciences—the changes which are far-reaching enough to be called revolutionary. But the full significance of this intellectual upheaval will become clear only if we compare it to another scientific revolution which took place in the sixteenth and seventeenth centuries. The significance of this first scientific revolution is fully recognized by the historians of science and historians in general; if I shall recall its main features, it will be only to provide us with a contrasting backdrop against which the salient features of the contemporary transformation of physics will stand out more vividly and more suggestively. The comparison between what is going on now and what went on three centuries ago will clearly show that the distance along which physical science moved in the last fifty years is not only greater than that covered in the last three centuries, but also—and this is far more significant— greater than the distance separating the science of Newton from that of Aristotle. In other words, the twentieth century revolution is far more profound than what was rather inappropriately called “the Copernican revolution;” the intellectual distance between Aristotle and Newton is far smaller than the distance separating the world of Newton and Laplace from that of Einstein, Planck, de Broglie, and Heisenberg.

Three sepiolite clays studied showed evidence for the presence of structural hydroxyl groups in three to five different environments depending on the composition of the clay. A 3720 cm−1 i.r. frequency is shown to be characteristic of SiOH at crystal edges which are very abundant in sepiolites. This band has not been seen by most workers because the Nujol, fluorolube or KBr used in sample preparation perturb it sufficiently to obscure it under other OH stretching bands. The 3680 cm−1 band is confirmed as being from the (Mg)3OH and evidence of a very small band near 3640 cm−1 is suggested to arise from limited trioctahedral substitution. The very crystalline Ampandrandava sepiolite shows only the above three bands. The intermediately crystalline Vallecas shows a 3620 cm−1 band in addition which is characteristic of dioctahedral systems and is due to either some vacancy sites or to the presence of attapulgite. This dioctahedral band is greater in the less crystalline Salinelles sepiolite; in addition, it has a smaller 3585 cm−1 band. Mg-Al-vacancy and Mg-Fe‴-vacancy are suggested as the source of the 3620 cm−1 and 3585 cm−1 bands.

It is customary to view the development of the Western economies as a straight line, leading from scarcity in the 19th century to affluence and abundance in the 20th. This interpretation neglects the dialectical reversal that took place and is taking place within a continuous development. The relative affluence and abundance of the Western economies is indeed the result of the economic system with all its institutions and its value-attitudes which emerged during and after the Industrial Revolution in the West. At the same time, this affluence was accompanied by a change in the character of its institutions, and especially also by a change in the underlying value-attitudes and in the style of life which it prescribes. The development was and is a truly dialectical one: the economics and psychology of scarcity and its institutions brought about an economics and psychology of affluence which is, in some respects, the antithesis of the economics and psychology of scarcity. This antithesis begins to undermine the institutional, psychological, and moral bases of the original system. A dialectical reversal is under way which shakes the foundations of our economic and moral order.

Artificial alteration of thirty-five trioctahedral and one dioctahedral micas by solutions varying in strength from 0·001 to 1·00 molal magnesium sulfate was found to approximate a normal exchange reaction after surface effects are eliminated. The equilibrium constants for the reaction:

$1/2M{g}^{2+}+K-mica=M{g}_{1/2}-mica+K^{+}\left(vermiculite\right)$$1/2 {Mg^{2+}}+K-mica=Mg_{1/2}-mica+K^+(vermiculite)$

range from 0·0001 to 0·0028 and average 0·0010 in value. X-ray diffraction study reveals that iron-rich micas tend to develop a 1:1 mixed-layer biotite-vermiculite structure in weak magnesium sulfate solutions whereas magnesium-rich biotite and phlogopite alter to vermiculite. Mica composition also influences the degree of alteration of mica to vermiculite. High fluorine and octahedral multivalent cation contents tend to retard the reaction whereas high magnesium content and perhaps high calcium contents tend to favor the alteration. The equilibrium constant data indicate that vermiculite and hydrobiotite are more stable than trioctahedral micas in most weathering environments.

At first sight, the situations of Venice and of Genoa seem to be almost as identical as mirror images. They are set at the head of the two deepest bays in the Mediterranean, both of them being virtually at the physical centre of that sea, and seemed fated by geography to act as rallying-points for East and West, and as bridge-heads for North and South. This, however, is not overly important: all countries, all nations are, in their own eyes, the physical centre of the Universe. The opportunity is always there, but it needs initiative to take advantage of it. For Venice, just as much as Genoa, had to overcome serious difficulties, both being almost cut off from their hinterland, Venice by the lagoons, Genoa by the mountains. Both cities were republics, and both ended up by having even the name of their supreme magistrate in common: the Doge. The merchandise that they exported and imported, the routes covered by their merchants, the currency, contracts, techniques, beliefs, and prejudices, only differed in a few details. The colonial empires were connected at several points. This made the wars between Venice and Genoa more fierce, but also made their ententes more intimate.

X-ray diffraction patterns obtained from montmorillonite-dextran complexes prepared with either B-512F or Polytran dextran showed maximum oven-dry crystal expansions of about 5·3 Å. X-ray diffraction patterns of individual complex preparations containing < 20 per cent dextran showed evidence of both expanded and collapsed crystals. The observation of expanded and collapsed crystals in individual preparations has not been previously reported and was apparently related to clay preparation. An estimate of the quantity of dextran which could be interacting with the silicate surface was obtained using polymer adsorption weights and volumes. At maximum adsorption almost all adsorbed B-512F could be in contact with the mineral surface, but only two thirds of the adsorbed Polytran could be in contact with the mineral surface.

What is art? —That which is common to all the arts. —But what do they have in common? —This (or especially this): their products invariably lend themselves to value judgements which stem from Aesthetics.

This reply, usually tacit but invariably understood, cannot, however, repress a further question, this time a rhetorical or an ironic one: and what does not lend itself to such judgements? The consensus omnium, acquired during the last two hundred years, can do no more than at best to mark an initial approach to the desired definition.

The combined use of electron microscopy and of selected area diffraction (SAD) has been applied to the study of montmorillonites from Wyoming and from Camp-Berteaux, of nontronite, and of hectorite. The study shows that only the elementary layers of the Wyoming montmorillonite and of the nontronite are single two-dimensional crystals. The elementary layers of the montmorillonite from Camp-Berteaux are formed by edge-to-edge associations of very small elements with mutual orientations of about 60° or multiples of 60°. The layers of hectorite are formed by edge-to-edge association of laths with fluctuations of orientation of the order of 10° rotation around adjoining edges. The SAD patterns of Wyoming montmorillonite show that the single layer plane symmetry group of this mineral is c1m1; nontronite layers belong to the symmetry group c2mm. The study of thick particles shows that in turbostratic smectites the layers are stacked with mutual rotations around the perpendicular to their plane. This mode of stacking explains the absence of hkl reflections. High resolution diffraction (HRD) patterns obtained with sample inclined to the electron beam show that only the structure of hectorite approaches the ideal model; nontronite and montmorillonite exhibit appreciable distortions with respect to the ideal model. HRD diagrams provide precise information for the refinement of the crystal structures of smectites

In the special theory of relativity, there is an unusual formula for addition of velocities. We will use this formula to generate Pythagorean triples. We define a Pythagorean triple in the usual manner as a triple of positive integers (a, b, c) such that a2 + b2 = c2. The numbers a and b are called legs, and c is called the hypotenuse. Later, we will allow b to take on the value of any integer. A primitive Pythagorean triple is a Pythagorean triple for which a, b and c are relatively prime.