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1949 ◽  
Vol 39 (1) ◽  
pp. 33-39
Author(s):  
A. G. Galanopoulos

Abstract Brief report of the macroseismic effects. Comparison of the distribution of the seismic effects with the strongly shaken area of the previous widespread earthquake of August 27, 1886. Critical discussion of the perceptibly shaken area, with the resulting suggestion that the depth of the focus may have been between 28 and 42 kilometers, greater than that of most destructive earthquakes of Greece. There is emphasized the lack of conductibility in the crystalline mass of Cyclades and, conversely, the activity of the Ionian-Cretan conducting line. The perfect coincidence of the locus of origin with the west trench fault of the Gulf of Messinia is taken as suggesting a tectonic origin.


The development of the enamel in Placental Mammals has always proved a difficult subject for investigation, principally because the change from the unaltered formative cell or ameloblast into the perfected enamel prism is so abrupt that the intermediate stage occupies only an exceedingly narrow zone. Indeed, many observers have supposed that the ameloblast cell undergoes a direct conversion into an enamel, without practically any intermediate transformation, whilst others have supposed that it secreted and shed out from its free end the material of which an enamel prism is composed, namely, an almost crystalline mass of calcium salts with a mere minute trace of organic substance. In a paper recently published in the ‘Philosophical Transactions’ (8), I showed that in the Implacental Mammals, in which the ultimate enamel contains a tube system, the transition from the unaltered ameloblast to the finished enamel was more gradual, and that it was possible to follow the steps of the process more satisfactorily owing to the persistence, for a time, in the forming enamel of conspicuous organic structures of definite form and arrangement. But in my opinion the two processes are not essentially different, and that which is easily seen in the marsupial may be used to elucidate that which is only with difficulty traceable in the placental group. But in a subsequent investigation into the formation of enamel in the Plagiostome fishes (9) I found an essential, and, indeed, an almost radical, difference, for in them the tissue which has generally been termed enamel is deposited in a thick and complete organic matrix, which presents the striking peculiarity of being furnished by the mesoblastic dentine papilla, and the claim of the tissue to be called enamel rests partly upon the immense development of the ameloblasts over it during the period of its calcification. This matrix is laid down of the full thickness of the ultimate enamel before any calcification in it takes place, and calcification is exceedingly rapid.


1878 ◽  
Vol 9 ◽  
pp. 712-713
Author(s):  
Crum Brown ◽  
J. Adrian Blaikie

In the former paper on this subject, the authors stated that when hyposulphite (thiosulphate) of trimethyl-sulphine is heated to about 135° C., it loses sulphide of methyl to the extent of 23·58 per cent., the salt at the same time fusing to a clear colourless liquid. On cooling, this solidifies to a hard, very hygroscopic crystalline mass.


1872 ◽  
Vol 20 (130-138) ◽  
pp. 277-289

In Part IV . of these researches reasons have been adduced for the following general conclusions, viz. that codeia and morphia are capable of forming polymerides (with the elimination of methyl in the case of codeia is some instances), which yield derivatives containing certainly not less than C 68 , and probably not less than C 130 (C 72 and C 144 in the case of those codeia derivatives where methyl has not been eliminated). Experiments now in progress tend to show that the formulae of codeia and morphia are really double of those formerly ascribed to these bases i, e . are C 30 H 42 N 2 O 6 and C 30 H 42 N 2 O 6 respectively, the proof of which is (as will be shown in a subsequent communication) that the first products of the action of hydrochloric acid on these bases appear to ‘contain chlorine and carbon in the proportions C 36 and Cl, C 34 and Cl respectively, instead of C 18 and Cl, C 17 and Cl. It might be anticipated, therefore, that intermediate polymerides might be form ed containing respectively :— Morphia series. Monomorphia.. C 34 H 38 N 206 Dimorphia . . . . C 68 H 70 N 4 O 12 Trimorphia.. . . C 102 H 104 N 6 O 18 Tetramorphia.. C 136 H 152 N 8 O 24 Codeia series. C 36 H 42 N 2 O 6 . . . Monocodeia. C 72 H 84 N 4 O 12 . . Dicodeia. C 108 H 126 N 6 O 6 . . Tricodeia. C 144 H 168 N 8 O 24 . . Tetracodeia. In the case of codeia these anticipations have been verified. In order to obtain these supposed polymerides before their alteration by secondary reactions, the action of acids other than a hydro acids was examined. Acetic acid seemed a probable agent for purpose ; but no appreciable quantity of any thing different from in codeia was obtained after sixty-four hours’ digestion a t 100° of one part this base with three parts of glacial acetic acid. On precipitation of product by Na 2 CO 3 in large excess, extraction with ether, and agitation of the ethereal extract with HCl, a crystalline mass was obtained while developed a smell of acetic acid on standing in contact with a slight excess of HCl ; but on analysis this gave numbers agreeing with those required codeia hydrochlorate, and from it nothing different from codeia could't obtained ; probably therefore only a trace of acetyl-codeia was formed.


1867 ◽  
Vol 15 ◽  
pp. 54-62 ◽  

The starting-point of the following experiments was an accidental obser­vation. Whilst investigating the chlorine-, bromine-, and nitro-derivatives of aniline, I had prepared a large quantity of phenylacetamide by the action of chloride of acetyl on aniline. From the hydrochlorate of aniline, abun­dantly produced as a by-product in this reaction, the aniline was recovered by treating the mother-liquors with hydrate of sodium. During the distil­lation, after the greater part of the aniline had passed over and collected in the receiver, a tenacious oily fluid began to come over, adhering to the tube of the condenser and gradually becoming a crystalline mass. It was easily purified by washing with cold, and crystallization from hot alcohol. Beautiful white leafy crystals were thus obtained, fusible at 137°, and volatile without decomposition at a temperature beyond the range of the mercury-thermometer. These crystals are almost insoluble in water, diffi­cultly soluble in cold, but soluble in hot alcohol, and also soluble in ether. The solutions are neutral.


1859 ◽  
Vol 9 ◽  
pp. 229-231

In a former Note addressed to the Royal Society (Proceedings, vol. ix. p. 150), I have alluded to some [new alkaloids which are pro­duced by the action of the bromides of triatomic alcohols upon the primary amidogen bases. I have since examined more minutely one of these bodies. At the common temperature, chloroform and aniline may be left in contact for a considerable time without any change becoming perceptible. Even at the temperature of boiling water scarcely any reaction takes place. But on exposing for ten or twelve hours a mixture of about equal volumes of chloroform and aniline in sealed tubes to a tem­perature of 180° or 190° C., a hard brown crystalline mass is ob­tained, which consists chiefly of the hydrochlorates of aniline and of a new crystalline base.


1859 ◽  
Vol 9 ◽  
pp. 277-283

While engaged in some experiments on the action of bibromide of ethylene on ammonia, a short account of which I have lately communicated to the Royal Society, I induced Mr. Henry Bassett, then working in my laboratory, to study the deportment of the same bromide with aniline, a characteristic representative of the class of primary monamines. In the following pages I propose to submit to the Society Mr. Bassett’s observations, together with the results of a series of experiments which I carried out myself after Mr. Bassett by circumstances had been prevented from a further continuation of the inquiry. A mixture of 1 volume of the bibromide of ethylene and 2 volumes of aniline, when exposed to the temperature of boiling water for an hour or two, solidifies into a crystalline mass of more or less solidity This mass is chiefly hydrobromate of aniline; it contains, however, in addition, three new organic bases, partly free, partly in the form of hydrobromates. These substances are formed in very "different quantities,—a beautiful crystalline body, difficultly soluble in alcohol, being invariably the chief product of the reaction, while the two other bases, the one solid but extremely soluble in alcohol, the other likewise solid but quite insoluble in this liquid, are found to be present in much smaller proportions.


The experiments of which the results are detailed in this paper, were made principally on the fluid which is found to be deposited in considerable quantity when oil-gas is compressed. This fluid, as obtained at the works of the Portable Oil-gas Company, is colourless, of a specific gravity less than that of water; insoluble in water except in very minute quantities; soluble in alcohol, ether, oils, &c.; and combustible, burning with a dense flame. It is strikingly distinguished from the oil from which it originated, by not being acted upon to any extent by solutions of the alkalies. Part of this fluid is very volatile, causing the appearance of ebullition at temperatures of 50° or 60°; other parts are more fixed, requiring even 250°, or above, for ebullition. By repeated distillations a series of products were obtained from the most to the least volatile, the most abundant being such as occurred from 170° to 200°. On subjecting these, after numerous rectifications, to a low temperature, it was found that some of them concreted into a crystalline mass, and ultimately a substance was obtained from them, principally by pressure at low temperatures, which upon examination proved to be a new compound of carbon and hydrogen. At common temperatures it appears as a colourless transparent liquid, of specific gravity 0·85, at 60°; having the general odour of oil-gas. Below 42° it is a solid body, forming dendritical transparent crystals, and contracting much during its congelation. At 0° it appears as a white or transparent substance, brittle, pulverulent, and of the hardness nearly of loaf-sugar. It evaporates entirely in the air: when raised to 186° it boils, furnishing a vapour, which has a specific gravity of 40, compared to hydrogen as 1. At a higher temperature the vapour is decomposed, depositing carbon. The substance is combustible, liberating charcoal if oxygen be not abundantly present. Potassium exerts no action upon it below 186°.


1828 ◽  
Vol 11 (1) ◽  
pp. 114-118
Author(s):  
Thomas Graham

The phenomenon referred to has long been known, and popularly exhibited in the case of Glauber's salt, without any adequate explanation. A phial or flask is filled with a boiling saturated solution of sulphate of soda or Glauber's salt, and its mouth immediately stopped by a cork, or a piece of bladder is tied tightly over it, while still hot. The solution, thus protected from the atmosphere, generally cools without crystallizing, although it contains a great excess of salt, and continues entirely liquid for hours and even days. But upon withdrawing the stopper, or puncturing the bladder, and admitting air to the solution, it is immediately resolved into a spongy crystalline mass, with the evolution of much heat. The crystallization was attributed to the pressure of the atmosphere suddenly admitted, till it was shewn that the same phenomenon occurred, when air was admitted to a solution already subject to the atmospheric pressure. Recourse was likewise had to the supposed agency of solid particles floating in the air, and brought by means of it into contact with the solution; or it was supposed that the contact of gaseous molecules themselves might determine crystallization, as well as solid particles. But although the phenomenon has been the subject of much speculation among chemists, it is generally allowed that no satisfactory explanation of it has yet been proposed.


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