scholarly journals On the refraction and dispersion of krypton and xenon and their relation to those of helium and argon

1908 ◽  
Vol 81 (549) ◽  
pp. 440-448 ◽  
Keyword(s):  
Royal Society ◽  
Wave Length ◽  
Chemical Society ◽  
The Other ◽  
Refractive Indices ◽  
Mercury Lamp ◽  
Bright Band ◽  
Point Of Departure ◽  
Micrometer Eyepiece ◽  
Contrary Direction

By the kindness of Sir William Ramsay and Prof. R. B. Moore, we have been enabled to measure the refractive indices of krypton and xenon with much larger quantities of these gases than were available at the time of their first isolation. The method of preparation of the gases will be given by Prof. Moore in a paper about to be presented to the Chemical Society. The procedure followed in determining the indices is described in a paper lately published by the Royal Society, and need be only briefly recapitulated. Jamin’s refractometer was used, and the source of light was, for the refraction, a Bastian mercury lamp, and for the dispersion, a Nernst lamp in conjunction with a fixed-deviation spectroscope. In measuring the dispersion, one of the two tubes was filled with the gas in question, and the other with air at such a pressure that the optical lengths of path of the two interfering rays were approximately equal. The light was then continuously changed from λ = 6500 to λ = 5000, and the change in the position of the centre of a given bright band was observed in a telescope fitted with a micrometer eyepiece. The distance on the same scale between the centres of two adjacent bright bands of known wave-length (generally λ = 5461) was also noted. These observations constituted the point of departure. The pressure of the gas in one tube was then altered till a convenient number of bands of wavelength 6500 (usually 85) had passed in one direction; and, next, the pressure of air in the other tube was altered till the same number of bands had passed in the contrary direction. The wave-length of the light was then changed from the first wave-length to the second, and the movement of the centre of the bright band under observation was again noted.

scholarly journals V. A letter on a canal in the medulla spinalis of some quadrupeds

1809 ◽  
Vol 99 ◽  
pp. 146-147
Keyword(s):  
Royal Society ◽  
Human Subject ◽  
Cauda Equina ◽  
The Other ◽  
Small Stream ◽  
Spinal Marrow ◽  
The Brain ◽  
Contrary Direction

Sir, According to your request, I send you an account of the facts I have ascertained, respecting a canal I discovered in the year 1803, in the medulla spinalis of the horse, bullock, sheep, hog, and dog; and should it appear to you deserving of being laid before the Royal Society, I shall feel myself particularly obliged, by having so great an honour conferred upon me. Upon tracing the sixth ventricle of the brain, which corresponds to the fourth in the human subject, to its apparent termination, the calamus scriptorius, I perceived the appearance of a canal, continuing by a direct course into the centre of the spinal marrow. To ascertain with accuracy whether such structure existed throughout its whole length, I made sections of the spinal marrow at different distances from the brain, and found that each divided portion exhibited an orifice with a diameter sufficient to admit a large sized pin; from which a small quantity of transparent colourless fluid issued, like that contained in the ventricles of the brain. The canal is lined by a membrane resembling the tunica arachnoidea, and is situated above the fissure of the medulla, being separated by a medullary layer: it is most easily distinguished where the large nerves are given off in the bend of the neck and sacrum, imperceptibly terminating in the cauda equina. Having satisfactorily ascertained its existence through the whole length of the spinal marrow, my next object was to discover whether it was a continued tube from one extremity to the other: this was most decidedly proved, by dividing the spinal marrow through the middle, and pouring mercury into the orifice where the canal was cut across, it passed in a small stream, with equal facility towards the brain (into which it entered), or in a contrary direction to where the spinal marrow terminates.

scholarly journals The reflection of X-rays by crystals. (II.)

1913 ◽  
Vol 89 (610) ◽  
pp. 246-248 ◽  
Keyword(s):  
Crystal Structure ◽  
Rock Salt ◽  
Royal Society ◽  
Wave Length ◽  
The Other ◽  
X Rays ◽  
Elementary Volume ◽  
Four Corners ◽  
Homogeneous Beam

This note is a supplement to a paper on the reflection of X-rays by crystals which has been recently communicated to the Royal Society. It is there shown that the wave-length of a homogeneous beam of X-rays can be found accurately in terms of the spacing of the elements of a crystal. There has been some doubt as to the actual arrangement of the atoms in the crystal and in consequence it was not possible in the paper quoted to draw any final conclusions as to wave-length values. From the work now described by W. L. Bragg it appears that the reflection phenomena lead to a more definite knowledge of crystal structure, and we may now complete various quantitative determinations. The elementary volume in rock-salt is a cube with 1 atom of sodium at each of four corners and 1 atom of chlorine at each of the other four. In other words the number of elementary volumes in any space of measurable dimensions is equal to the number of atoms in that space.

On the refractive indices and densities of normal and semi-normal aqueous solutions of hydrogen chloride and the chlorides of the alkalis

1899 ◽  
Vol 64 (402-411) ◽  
pp. 308-318 ◽  
Keyword(s):  
Aqueous Solutions ◽  
Hydrogen Chloride ◽  
Royal Society ◽  
Chemical Society ◽  
Inorganic Salts ◽  
Refractive Indices ◽  
Uniform Temperature ◽  
Different Temperatures

A very large number of observations have been made of the refractive indices and densities of aqueous solutions of inorganic salts and acids: in England, more especially, by Dr. J. H. Gladstone, who in a paper in the ‘Philosophical Transactions’ for 1870, gave the values he had obtained for the refractive indices and densities of some 160 salts and acids; and in a series of papers published subsequently in the 'Journal of the Chemical Society,’ has given the results of further observations. Most, however, of these determinations have been made with solutions of different strengths, and at different temperatures, and, therefore, I venture to bring before the Royal Society an account of some observations I have made of the refractive indices and densities of normal and semi-normal aqueous solutions of hydrogen chloride, and the chlorides of the alkalis at a uniform temperature of 18°.

Considerations about Semitic Etyma in de Vaan’s Latin Etymological Dictionary: Terms for Plants, Domestic Animals, Tools or Vessels

Philology ◽  
2019 ◽  
Vol 4 (2018) ◽  
pp. 35-156
Author(s):  
EPHRAIM NISSAN
Keyword(s):  
Domestic Animals ◽  
The Other ◽  
Etymological Dictionary ◽  
Point Of Departure

Abstract In this long study, our point of departure is particular entries in Michiel de Vaan’s Latin Etymological Dictionary (2008). We are interested in possibly Semitic etyma. Among the other things, we consider controversies not just concerning individual etymologies, but also concerning approaches. We provide a detailed discussion of names for plants, but we also consider names for domestic animals.

Editorial

2018 ◽  
Vol 6 (16) ◽  
pp. 11
Author(s):  
Andrea Meza Torres
Keyword(s):  
Social Sciences ◽  
Theoretical Perspective ◽  
Interreligious Dialogue ◽  
The Other ◽  
Intercultural Dialogue ◽  
Enrique Dussel ◽  
Point Of Departure

The essays in this dossier are the result of the course  “Interreligious and intercultural dialogue from a decolonial perspective”, which took place between May and June 2017 at the CEIICH in the UNAM. In this course, I proposed to link a decolonial theoretical perspective to the topic of “intercultural dialogue” and, beyond, to “interreligious dialogue”; anyhow, this last topic turned out to be the point of departure to explore more profound dialogues, linked no only to religious phenomena but to sacred traditions and spiritualities. During the course, emphasis was put on this last aspect due to the fact that the topic of “the Divine” (in its different expressions), although central to decoloniality, has been poorly studied. Moreover, it has been marginalized within secularized social sciences —and this not just in Mexico, but in most occidentalized universities throughout the globe. This vacuum towards the study of “the Divine” —and, beyond, its limitation through a concept of culture (which is, at the same time, associated to the colonized and to the “other” of modernity)— led the participants of this volume to research deeper that which philosopher Enrique Dussel has described as the “spaces denied and oppressed by modernity”.

Når styringens ambitioner udfordres af praksis. Om at analysere rummet imellem styringens intentioner og situationel praksis

2016 ◽  
Vol 27 (1) ◽  
pp. 15-34 ◽  
Author(s):  
Mathias Herup Nielsen ◽  
Niklas Andreas Andersen
Keyword(s):  
Michel Foucault ◽  
Qualitative Interviews ◽  
The Other ◽  
Empirical Reality ◽  
Men I ◽  
Unemployment Policy ◽  
The Relationship ◽  
Point Of Departure ◽  
Local Employment

Studier, der analyserer det sociale med inspiration fra Foucaults tanker om governmentality, kritiseres i stigende omfang for at afskære sig fra at analysere de praktiske relationer, som politisk styring konkret indlejres i. I artiklen tager vi afsæt i denne kritik og viser, med et studie af forholdet mellem et kommunalt jobcenter og et lokalt beskæftigelsesråd, hvordan governmental magtanalyse kan indfange styringens uforudsigelige, mangefacetterede og immanente karakter ved at fokusere på styringsintentionernes møde med den praktiske virkelighed, der søges styret. Formelt er rådet nedsat til at overvåge og kontrollere jobcentret, men i den praktiske relation er det snarere jobcentret, som overvåger og kontrollerer rådet. Artiklen viser, hvordan dette er muligt ved at analysere jobcentrets arbejde med rådet ved hjælp af en række centrale begreber fra Foucaults forfatterskab. Empirisk trækker studiet foruden formelle myndighedsdokumenter, der beskriver rådets tiltænkte rolle, på praksisinformerende empiri i form af kvalitative interviews og mødereferater over en fire-årig periode. ENGELSK ABSTRACT: Mathias Herup Nielsen and Niklas Andreas Andersen: When Praxis Challenges the Ambitions of Governing. Analyzing the Space between the Intentions of Governing and Situational Praxis Studies working with the Foucauldian concept of ”governmentality” are frequently criticized for their apparent disregard of empirical reality. This article takes this critique as its point of departure and demonstrates the application of the concept of governmentality in a concrete empirical case study in order to grasp the unpredictable and multifaceted nature of modern day power. The case investigated here is the relationship between a Danish Jobcentre and a so-called local employment council (LBR). The latter was created to ”control” and ”monitor” the former organization. However, in practice, it is rather the other way around – the Jobcentre is controlling and monitoring the members of the LBR. This article draws on a number of well-known Foucauldian concepts to show how this relation of power is practically structured. Empirically the article draws on documents from central authorities as well as on a number of qualitative interviews with the actors involved – hence, the article attempts to meet with the dominant overall critique of the governmentality perspective for disregarding empirical reality. Keywords: governmentality, Michel Foucault, unemployment policy, jobcentre.

scholarly journals Description of a new barometer, recently fixed up in the apart­ments of the Royal Society; with remarks on the mode hitherto pursued at various periods, and an account of that which is now adopted, for correcting the observed height of the mercury in the society’s barometer

1843 ◽  
Vol 4 ◽  
pp. 1-3
Keyword(s):  
Royal Society ◽  
The Other ◽  
Chemical Effect ◽  
The Absolute ◽  
The One ◽  
And Control ◽  
Usual Scale

The barometer, here alluded to, may in some measure be consi­dered as two separate and independent barometers, inasmuch as it is formed of two distinct tubes dipping into one and the same cistern of mercury. One of these tubes is made of flint glass, and the other of crown glass, with a view to ascertain whether, at the end of any given period, the one may have had any greater chemical effect on the mercury than the other, and thus affected the results. A brass rod, to which the scale is attached, passes through the framework, between the two tubes, and is thus common to both : one end of which is furnished with a fine agate point, which, by means of a rack and pinion moving the whole rod, may be brought just to touch the surface of the mercury in the cistern, the slightest contact with which is immediately discernible; and the other end of which bears the usual scale of inches, tenths, &c.; and there is a separate vernier for each tube. A small thermometer, the bulb of which dips into the mercury in the cistern, is inserted at the bottom : and an eye­piece is also there fixed, so that the agate point can be viewed with more distinctness and accuracy. The whole instrument is made to turn round in azimuth, in order to verify the perpendicularity of the tubes and the scale. It is evident that there are many advantages attending this mode of construction, which are not to be found in the barometers as usu­ally formed for general use in this country. The absolute heights are more correctly and more satisfactorily determined ; and the per­manency of true action is more effectually noticed and secured. For, every part is under the inspection and control of the observer; and any derangement or imperfection in either of the tubes is imme­diately detected on comparison with the other. And, considering the care that has been taken in filling the tubes, and setting off the scale, it may justly be considered as a standard barometer . The pre­sent volume of the Philosophical Transactions will contain the first register of the observations that have been made with this instru­ment.

Robert Hooke: A fractographic study of Kettering–stone

1997 ◽  
Vol 51 (1) ◽  
pp. 45-55 ◽  
Author(s):  
Derek Hull
Keyword(s):  
Royal Society ◽  
The Other ◽  
Microscopical Observation ◽  
Robert Hooke ◽  
Fractographic Study

Observ. XV. illustrated by Schem. IX. Figur:1 (figure 1 of this paper) in Robert Hooke's Micrographia (1665)1 is a description of Kettering–stone ‘which is brought from Kettering in Northampton–shire, and digg’d out of a Quarry, as I am inform'd’. As Curator of Experiments for the Royal Society from 1662, Hooke was charged by the Society to bring in at every meeting one microscopical observation at least. The minutes of the Society2 record that on 15 April 1663 ‘Mr Hooke showed the Company two Microscopicall Schemas; one representing the Pores of Cork … the other a Kettering Stone, appearing to be composed of Globules; and those hollow ones, each having 3 Coatings, sticking to one another, and so making up one entire firm stone’.

scholarly journals Interferential comparison of the red and other radiations emitted by a new cadmium lamp and the michelson lamp

1933 ◽  
Vol 139 (837) ◽  
pp. 202-218 ◽  
Keyword(s):  
Fine Structure ◽  
High Temperature ◽  
Wave Length ◽  
The Other ◽  
Reference Standard ◽  
Definite Evidence ◽  
Electro Magnetic ◽  
The Many ◽  
Red Radiation ◽  
Red Line

It is now generally recognised that future definitions of the units of length will probably be based on the length of a wave of visible light. At present the wave-length of the red radiation of cadmium serves as the basis of all measurements of the lengths of electro-magnetic waves which are perceptible by optical means, and provisional sanction has been given to measurements of length on the same basis, as an alternative to direct reference to the metre. Whether the cadmium red radiation provides the best reference standard for all measurements of length has not yet been definitely established. Two international committees, one representing spectroscopists and the other metrologists, have sanctioned standard specifications for cadmium lamps of the Michelson type from which the red radiation may be produced. The two specifications differ from one another in certain details, but both are subject to the same objections. These objections are directed partly against the high temperature at which it is necessary to run the lamp and partly against the high voltage required to excite the radiation. Therefore, such hyperfine structure and asymmetry as may be present in the red line of cadmium is likely to be masked in the Michelson lamp by a combination of two phenomena —the enhanced Doppler effect due to the high temperature of the radiating cadmium atoms, and the effect of the moderately high intensity of the electric field. Were this not so, it might be somewhat surprising that no definite evidence of fine structure or asymmetry had so far been observed in the red line from the Michelson lamp, notwithstanding the many careful examinations, with the aid of the most sensitive interferometers, to which this line has been subjected, in view of its importance as the reference standard for all other wave-lengths. Recently Nagaoka and Sugiura have recorded that they have observed slight evidences of structure in the red radiation when excited under special conditions in which great precautions were taken to ensure extreme sharpness of the line. It is believed, however, that no subsequent confirmation of this effect has yet been published.

XXIII. On the water-barometer erected in the hall of the Royal Society

1832 ◽  
Vol 122 ◽  
pp. 539-574 ◽  
Keyword(s):  
Royal Society ◽  
Physical Science ◽  
The Other ◽  
Metallic Tube ◽  
French Academy ◽  
History Of ◽  
The Subject ◽  
The Common ◽  
Academy Of Sciences ◽  
Made In

I have for some time entertained an opinion, in common with some others who have turned their attention tot he subject, that a good series of observations with a Water-Barometer, accurately constructed, might throw some light upon several important points of physical science: amongst others, upon the tides of the atmosphere; the horary oscillations of the counterpoising column; the ascending and descending rate of its greater oscillations; and the tension of vapour at different atmospheric temperatures. I have sought in vain in various scientific works, and in the Transactions of Philosophical Societies, for the record of any such observations, or for a description of an instrument calculated to afford the required information with anything approaching to precision. In the first volume of the History of the French Academy of Sciences, a cursory reference is made, in the following words, to some experiments of M. Mariotte upon the subject, of which no particulars appear to have been preserved. “Le même M. Mariotte fit aussi à l’observatoire des experiences sur le baromètre ordinaire à mercure comparé au baromètre à eau. Dans l’un le mercure s’eléva à 28 polices, et dans Fautre l’eau fut a 31 pieds Cequi donne le rapport du mercure à l’eau de 13½ à 1.” Histoire de I'Acadérmie, tom. i. p. 234. It also appears that Otto Guricke constructed a philosophical toy for the amusement of himself and friends, upon the principle of the water-barometer; but the column of water probably in this, as in all the other instances which I have met with, was raised by the imperfect rarefaction of the air in the tube above it, or by filling with water a metallic tube, of sufficient length, cemented to a glass one at its upper extremity, and fitted with a stop-cock at each end; so that when full the upper one might be closed and the lower opened, when the water would fall till it afforded an equipoise to the pressure of the atmo­sphere. The imperfections of such an instrument, it is quite clear, would render it totally unfit for the delicate investigations required in the present state of science; as, to render the observations of any value, it is absolutely necessary that the water should be thoroughly purged of air, by boiling, and its insinuation or reabsorption effectually guarded against. I was convinced that the only chance of securing these two necessary ends, was to form the whole length of tube of one piece of glass, and to boil the water in it, as is done with mercury in the common barometer. The practical difficulties which opposed themselves to such a construction long appeared to me insurmount­able; but I at length contrived a plan for the purpose, which, having been honoured with the approval of the late Meteorological Committee of this Society, was ordered to be carried into execution by the President and Council.

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