II. Researches on explosives.—Fired gunpowder

1875 ◽  
Vol 165 ◽  
pp. 49-155 ◽  
Keyword(s):  
Considerable Time ◽  
Short Account ◽  
Secretary Of State ◽  
Series Of Experiments ◽  
The Subject ◽  
The Difference ◽  
Difficult Subject ◽  
Physical Fact

The investigations which form the subject of this memoir have occupied our attention for a considerable time, having been commenced in 1868. They have been made collaterally with a series of experiments carried on by a Committee appointed by the Secretary of State for War, with the view, among other objects, of determining the most suitable description of powder for use in heavy ordnance, which is still continually increasing in-size; indeed our main object has been to endeavour to throw additional light upon the intricate and difficult subject under investigation by that Committee. There are perhaps few questions upon which, till within quite a recent date, such discordant opinions have been entertained as upon the phenomena and results which attend the combustion of gunpowder. As regards the question alone of the pressure developed, the estimates are most discordant, varying from the 1000 atmospheres of Robins to the 100,000 atmospheres of Rumford; or even, discarding these extreme opinions in favour of views which have been accepted in modern text-books as more reliable, the difference between an estimate of 2200 and of 29,000 atmospheres is sufficiently startling as regards a physical fact of so much importance. The views regarding the decomposition of gunpowder are nearly as various; and we therefore think that a description and discussion of our own researches may be usefully preceded by a short account of the labours of the previous investigators of this subject and of the grounds upon which their conclusions were based.

scholarly journals Observations made with the invariable pendulum (No. 4. Jones), at the royal observatory, cape of good hope, for the purpose of determining the compression of the earth

1833 ◽  
Vol 2 ◽  
pp. 396-397
Keyword(s):  
Considerable Time ◽  
Cape Of Good Hope ◽  
The Earth ◽  
Direct Measurements ◽  
Royal Observatory ◽  
Figure Of The Earth ◽  
Geographical Position ◽  
Series Of Experiments ◽  
Independent Series ◽  
The Difference

Of the two methods employed for determining the figure of the earth, namely, the direct measurements of arcs of the meridian, or of ascertaining the variations in the length of the seconds pendulum in different places, the author remarks that the former is attended with the collateral benefit of fixing the geographical position of certain stations in the country surveyed; but the latter possesses the advantage of enabling the observer to concentrate, under his own immediate eye, the results of his inquiries. The Observatory at the Cape of Good Hope having been furnished by the Lords Commissioners of the Admiralty with the invariable pendulum of Jones, which had for several years been strictly examined by Capt. Sabine, the author was anxious to begin a series of experiments with it; and as it was not likely that the observatory would be completed for a considerable time, he caused a strong brick pier to be built in an adjoining outhouse for the support of a transit instrument, the same which he had used in forming his catalogue of southern stars. He gives a detailed account of his mode of fitting up the clock, and other parts of the apparatus necessary for the pendulum experiments. He was ably assisted by Capt. Ronald and Lieut. Johnson, who took an active part in all the observations. He remarks, that the near agreement of the three independent series of observations, made by himself and these two gentlemen, and which accompany the paper, is no small argument in favour of their accuracy. The difference in the number of vibrations of the seconds pendulum at the Cape, from that in London, in a mean solar day, he finds to be 67·12, from which it results that the compression of the earth is 1/288.5. The author is of opinion that the invariable pendulum ought to be a standard instrument in every observatory; that it should be swung at all seasons of the year, and occasionally transferred to various fixed observatories in both hemispheres, and returned again to its original station, where it should undergo a renewed and rigid examination before it is sent round on a fresh circuit of these stations.

scholarly journals On the intensity of light reflected from transparent substances

1907 ◽  
Vol 79 (527) ◽  
pp. 18-30 ◽  
Keyword(s):  
Polished Glass ◽  
Reflected Light ◽  
Experimental Errors ◽  
Series Of Experiments ◽  
The Subject ◽  
The Difference ◽  
Reflecting Surface ◽  
Crucial Test ◽  
Careful Comparison ◽  
Theory And Experiment

A careful comparison of theory with experiment as regards the intensity of reflection would seem to suggest itself naturally as a crucial test of the validity of any optical theory. In spite of this, it was not till late in the last century that the problem was seriously undertaken by experimentalists. In 1870 Rood turned his attention to. the subject with the view of testing Fresnel’s laws, and concluded from his experiments “that the reflecting power of glass conforms, in the closest manner, to the predictions of theory.” However, in 1886, this conclusion was shown to be untenable by Lord Rayleigh. The difficulties of measuring the intensity of the reflected light accurately are very considerable, and Rood had contented himself with estimating the transmitted light and deducing the amount that was reflected. Rayleigh showed that when this fact was considered the difference between Fresnel’s formula and Rood’s experimental results might amount to 7 per cent, of the reflected light, a difference much too great to be regarded as insignificant. Rayleigh found from his own experiments that recently polished glass has a reflecting power differing not more than 1 or 2 per cent, from Fresnel’s formula; but that after some months or years the reflection may fall off 10 per cent, or more, and that without any apparent tarnish. About the same time Sir John Conroy carried out a lengthy series of experiments on the same subject. His results were published in the ‘Phil. Trans.,’ 1888, and confirmed those of Lord Rayleigh. There can thus be no doubt of a decided departure from Fresnel’s formula under certain circumstances. The difference is too great to be put down to experimental errors, and there is no evidence of such errors, seeing that the results of experiment are fairly consistent. Nor can there be very much doubt as to the direction in which to look for an explanation of the apparent divergence between theory and experiment. Everything points to a changing condition of the reflecting surface, and this suggests that a consideration of the layer of transition will show how Fresnel’s laws are departed from in this as in some other directions. The object of the present paper is to investigate this matter rather more systematically than appears to have been done hitherto.

scholarly journals III. Contributions to the anatomy of the central nervous system of plagiostomata

1886 ◽  
Vol 40 (242-245) ◽  
pp. 10-14 ◽  
Keyword(s):  
Central Nervous System ◽  
Nervous System ◽  
Cranial Nerves ◽  
Macroscopic Appearance ◽  
Short Account ◽  
The Third ◽  
Branchial Arches ◽  
The Central Nervous System ◽  
The Subject ◽  
The Difference

After referring to the literature of the subject, the author gives a short account of the macroscopic appearance of the brains of the following species of Plagiostomata, viz., Raja batis, Rhina squatina, Scyllium catulus , and Acanthias vulgaris . He then refers to the distribution of the cranial nerves, especially of the trifacial and vagus, pointing out the resemblance of the distribution of the last-mentioned nerve in Rhina to that described by Gegenbaur in Hexanthus; the difference lying in the fact that in the former the rami branchiales of this nerve, the number of which correspond the number of the branchial arches, divide into two terminal branches only, the rami anteriores and posteriores, the third, the rami pharyngei, being absent.

scholarly journals XXXVII. Experimental researches on the conductive powers of various substances, with the application of the results to the problem of terrestrial temperature

1857 ◽  
Vol 147 ◽  
pp. 805-849 ◽  
Keyword(s):  
Considerable Time ◽  
Future Paper ◽  
Series Of Experiments ◽  
The Subject ◽  
Government Grant ◽  
The Many ◽  
Experimental Researches

In presenting this memoir to the Society, I feel myself called upon to acknowledge the liberal aid which I have received from the Committee for the disposal of the Annual Government Grant for the Advancement of Science, in the prosecution of the experimental researches in which I have been engaged for a considerable time. The present paper contains an account of a part only of my experiments, with the application of the results of them to the problem of terrestrial temperature. An account of the remaining experiments will be reserved for a future paper. I am likewise bound to express in the strongest terms my obligations to my friends Mr. Fairbairn and Mr. Joule. Without the aid of the former of these gentlemen I should have been unable even to commence the series of experiments which I have now nearly concluded; and among the many ways in which this assistance has been so promptly rendered, I may mention his having constantly placed at my disposal the invaluable services of one of his principal workmen, William Ward, without whose untiring activity and mechanical resources, I should have utterly despaired of bringing my experiments to any successful issue. The value of Mr. Joule’s assistance, especially in the commencement of these experiments, will be understood by those who are acquainted with his sound philosophical knowledge and experimental skill. More specific acknowledgement of his services will be called for in my next communication. I now proceed to the subject of this paper.

Differences in mechanisms of intelligence among vertebrates

1985 ◽  
Vol 308 (1135) ◽  
pp. 53-65 ◽  
Keyword(s):  
Comparative Research ◽  
Rank Order ◽  
Vertebrate Species ◽  
Rapid Improvement ◽  
Series Of Experiments ◽  
The Subject ◽  
The Difference ◽  
Efficient Learning ◽  
Learning Sets ◽  
Serial Reversal

Much comparative research aimed at establishing differences in intelligence among vertebrates has failed to convince the sceptic, because it has concentrated on a single experimental paradigm (such as learning sets), while employing a diverse array of species in the hope of establishing a rank ordering of intelligence. The sceptic can insist that such research has not even established that there are any differences in mechanisms of intelligence between any pair of vertebrate species, let alone elucidated the nature of the difference, and even the unsceptical will doubt that such research is ever likely to establish a rank order of intelligence. It is more informative to concentrate on fewer species, but a broader range of experimental paradigms. Thus, studies of serial reversal learning have consistently suggested that goldfish do not show such rapid improvement as do rats. One explanation of this might be that rats learn more effectively than goldfish to use the outcome of one trial to predict the outcome of the next. The suggestion is supported by finding other experimental paradigms, such as alternation learning, which must also tap such a process, and where rats again learn more rapidly than goldfish. Efficient learning-set performance may also depend on this process, but must in addition require the subject to transfer this rule across changes of stimuli. There is reason to believe that not all vertebrates are equally adept at such transfer, and this possibility is explored in a series of experiments studying the transfer of matchingto-sample in pigeons and corvids. The corvids display significantly better transfer and the close similarity in training procedures possible with these subjects makes it unlikely that this is due to differences in these training procedures.

Learning Language Levels in Students Accurate with a History Academic Achievement History

2017 ◽  
Vol 1 (2) ◽  
pp. 137
Author(s):  
Noorlela Binti Noordin ◽  
Abdul Razaq Ahmad ◽  
Anuar Ahmad
Keyword(s):  
Academic Achievement ◽  
Statistical Inference ◽  
Quantitative Data ◽  
Quantitative Methods ◽  
Descriptive Statistics ◽  
Language Test ◽  
The Subject ◽  
The Difference ◽  
Learning Language ◽  
The Relationship

This study was aimed to evaluate the Malay proficiency among students in Form Two especially non-Malay students and its relationship to academic achievement History. To achieve the purpose of the study there are two objectives, the first is to look at the difference between mean of Malay Language test influences min of academic achievement of History subject among non-Malay students in Form Two and the second is the relationship between the level of Malay proficiency and their academic achievement for History. This study used quantitative methods, which involved 100 people of Form Two non-Malay students in one of the schools in Klang, Selangor. This study used quantitative data were analyzed using descriptive statistics and statistical inference with IBM SPSS Statistics v22 software. This study found that there was a relationship between the proficiency of Malay language among non-Malay students with achievements in the subject of History. The implications of this study are discussed in this article.

The Idea of a Meaningful Synthesis of Marxist and Non-Marxist Systems of Political Economy as a Mirror of Intellectual Turmoil (About V.T. Ryazanov’s Book «Modern Political Economy: Prospects of Neo-Marxist Synthesis»)

2019 ◽  
pp. 74-98
Author(s):  
A.B. Lyubinin
Keyword(s):  
Economic Theory ◽  
Political Economy ◽  
Economic Status ◽  
Economic Science ◽  
Objective Reality ◽  
Commodity Production ◽  
Subjective Assessments ◽  
The Subject ◽  
The Difference ◽  
Political Economic

Review of the monograph indicated in the subtitle V.T. Ryazanov. The reviewer is critical of the position of the author of the book, believing that it is possible and even necessary (to increase the effectiveness of General economic theory and bring it closer to practice) substantial (and not just formal-conventional) synthesis of the Marxist system of political economy with its non-Marxist systems. The article emphasizes the difference between the subject and the method of the classical, including Marxist, school of political economy with its characteristic objective perception of the subject from the neoclassical school with its reduction of objective reality to subjective assessments; this excludes their meaningful synthesis as part of a single «modern political economy». V.T. Ryazanov’s interpretation of commodity production in the economic system of «Capital» of K. Marx as a purely mental abstraction, in fact — a fiction, myth is also counter-argued. On the issue of identification of the discipline «national economy», the reviewer, unlike the author of the book, takes the position that it is a concrete economic science that does not have a political economic status.

Research of the activity and viability of spermatozoa at different concentrations and proportions of diluents after incubation

2020 ◽  
pp. 88-95
Author(s):  
Svitlana Lobchenko ◽  
Tetiana Husar ◽  
Viktor Lobchenko
Keyword(s):  
Plasma Concentration ◽  
Incubation Time ◽  
Coefficient Of Variation ◽  
Incubation Medium ◽  
Wide Range ◽  
Series Of Experiments ◽  
The Subject ◽  
Boar Spermatozoa ◽  
Native Plasma ◽  
Better Than

The results of studies of the viability of spermatozoa with different incubation time at different concentrations and using different diluents are highlighted in the article. (Un) concentrated spermatozoa were diluented: 1) with their native plasma; 2) medium 199; 3) a mixture of equal volumes of plasma and medium 199. The experiment was designed to generate experimental samples with spermatozoa concentrations prepared according to the method, namely: 0.2; 0.1; 0.05; 0.025 billion / ml. The sperm was evaluated after 2, 4, 6 and 8 hours. The perspective of such a study is significant and makes it possible to research various aspects of the subject in a wide range. In this regard, a series of experiments were conducted in this area. The data obtained are statistically processed and allow us to highlight the results that relate to each stage of the study. In particular, in this article it was found out some regularities between the viability of sperm, the type of diluent and the rate of rarefaction, as evidenced by the data presented in the tables. As a result of sperm incubation, the viability of spermatozoa remains at least the highest trend when sperm are diluted to a concentration of 0.1 billion / ml, regardless of the type of diluent used. To maintain the viability of sperm using this concentration of medium 199 is not better than its native plasma, and its mixture with an equal volume of plasma through any length of time incubation of such sperm. Most often it is at this concentration of sperm that their viability is characterized by the lowest coefficient of variation, regardless of the type of diluent used, which may indicate the greatest stability of the result under these conditions. The viability of spermatozoa with a concentration of 0.1 billion / ml is statistically significantly reduced only after 6 or even 8 hours of incubation. If the sperm are incubated for only 2 hours, regardless of the type of diluent used, the sperm concentrations tested do not affect the viability of the sperm. Key words: boar, spermatozoa, sperm plasma, concentration, incubation, medium 199, activity, viability, rarefaction.

Rhythm

2018 ◽  
Author(s):  
Lexi Eikelboom
Keyword(s):  
Social Sciences ◽  
Twentieth Century ◽  
Human Existence ◽  
Embodied Experience ◽  
Giorgio Agamben ◽  
The Social ◽  
Contemporary Philosopher ◽  
The Subject ◽  
The Difference ◽  
Theoretical Category

This book argues that, as a pervasive dimension of human existence with theological implications, rhythm ought to be considered a category of theological significance. Philosophers and theologians have drawn on rhythm—patterned movements of repetition and variation—to describe reality, however, the ways in which rhythm is used and understood differ based on a variety of metaphysical commitments with varying theological implications. This book brings those implications into the open, using resources from phenomenology, prosody, and the social sciences to analyse and evaluate uses of rhythm in metaphysical and theological accounts of reality. The analysis relies on a distinction from prosody between a synchronic approach to rhythm—observing the whole at once and considering how various dimensions of a rhythm hold together harmoniously—and a diachronic approach—focusing on the ways in which time unfolds as the subject experiences it. The text engages with the twentieth-century Jesuit theologian Erich Przywara alongside thinkers as diverse as Augustine and the contemporary philosopher Giorgio Agamben, and proposes an approach to rhythm that serves the concerns of theological conversation. It demonstrates the difference that including rhythm in theological conversation makes to how we think about questions such as “what is creation?” and “what is the nature of the God–creature relationship?” from the perspective of rhythm. As a theoretical category, capable of expressing metaphysical commitments, yet shaped by the cultural rhythms in which those expressing such commitments are embedded, rhythm is particularly significant for theology as a phenomenon through which culture and embodied experience influence doctrine.

On the Structure of the Spiracles of a Tick—Haemaphysalis punctata, Canesteini and Fanzago

Parasitology ◽  
1908 ◽  
Vol 1 (4) ◽  
pp. 347-351 ◽  
Author(s):  
G. H. F. Nuttall ◽  
W. F. Cooper ◽  
L. E. Robinson
Keyword(s):  
Ixodes Ricinus ◽  
Detailed Structure ◽  
Short Account ◽  
Haemaphysalis Punctata ◽  
The Subject ◽  
Single Figure

The detailed structure of the spiracles in the Ixodoidea has hitherto received little or no attention at the hands of zoologists; at the same time, these organs are sufficiently extraordinary to make it a matter of surprise that, so far as our knowledge of the literature goes, not one of the numerous contributors to the subject of tick anatomy has found it worth while to undertake a complete description or to publish figures to illustrate it. Batelli (1891) gives a short account of the structure of the spiracle of a tick, presumably Ixodes ricinus, with a single figure, but with this exception we have been unable to find any further information on the subject.

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