scholarly journals XXIX. An account of some experiments to measure the velocity of electricity and the duration of electric light

1834 ◽  
Vol 124 ◽  
pp. 583-591 ◽  
Keyword(s):  
Electric Machine ◽  
Angular Motion ◽  
Continuous Line ◽  
Rapid Motion ◽  
Royal Institution ◽  
Series Of Experiments ◽  
The Subject ◽  
Electric Light ◽  
Rotatory Motion

The path of a luminous or an illuminated point in rapid motion, it is well known, appears as a continuous line, in consequence of the after duration of the visual im­pression. There is nothing, however, in the appearance of such a line by which the eye can determine either the direction or the velocity of the motion which generates it. It occurred to me some years since, that if the motion which described the line in these cases were to be compounded with another motion, the direction and velocity of which were known, it would be easy, from an inspection of the resultant straight or curved line, to determine the velocity and direction of the former. Following up this idea, I made a series of experiments relating to the oscillatory motions of sono­rous bodies, too numerous, and not sufficiently connected with the subject of the pre­sent communication, to be detailed in this place. The satisfactory results thus ob­tained made me desirous to ascertain whether, by similar means, some information might not be gained respecting the direction and velocity of the electric spark : the method by which I then proposed to effect this purpose was first announced in a lec­ture delivered by Dr. Faraday at the Royal Institution in June, 1830. My attention was again drawn to the subject at the commencement of last year, and I attempted to realize the idea in the following manner. Fig. 1 represents the apparatus employed, which was screwed at a to the spindle of a whirling machine, so that a rapid rotatory motion might be given to it. The upper and lower parts, which were all of brass except the wooden disc b c , were insulated from each other by a stout glass rod d e ; a slip of tinfoil connected the ball h with a , and the upper ball g was capable of adjustment to various distances from the lower one h . When the ball f was placed within striking distance of the prime conductor of an electric machine, a spark passed between them, and also between the balls g and h , which could be separated to the distance of four inches, so as to exhibit a spark of that length. It is obvious, that if the angular motion of the balls were in any sensible proportion to the velocity of electricity, there would be a deviation between the upper and lower terminations of the line. The instrument revolving from left to right, if the motion of the spark be downwards, the deflection of the line should be as in fig. 2; and if its motion be upwards, it should be deflected as in fig. 3.

Description of a percussion shell, to be fired horizontally from a common gun

1833 ◽  
Vol 2 ◽  
pp. 296-298
Keyword(s):  
Spiral Motion ◽  
Resisting Medium ◽  
Cylindrical Form ◽  
Air Blowing ◽  
Series Of Experiments ◽  
The Subject ◽  
Inclined Planes ◽  
Rotatory Motion ◽  
A Current ◽  
Made In

In this paper, the author first considers the theory of rifles, with which the subject of it is intimately connected; and regarding it as an admitted principle, that irregularities in the flight of shot arise from irregularities either in their surface or substance, shows how the rotatory motion of a rifle ball, by presenting every part uniformly to the action of the resisting medium, obviates the effect of these irregularities. The spiral or rotatory motion of the ball in rifles, is generally supposed to arise wholly from the re-action of the grooves in the barrel, or from the indentations made by them in the surface of the ball; but the author, taking into consideration the powerful action of the air on projectiles, is led to conclude that the rotation of a grooved ball may be sustained during its flight, or even produced originally by the resistance of the air acting on the inclined planes formed by the grooves, on the same principle as the rotation of the sails of a windmill. These considerations led the author to conceive the possibility of giving the spiral motion to grooved shot fired from a plain barrel; an idea which, he remarks, seems to have also occurred to Mr. Robins, who left, however, no clue to enable us to discover the nature of his plan. He accordingly commenced a series of experiments for the purpose, and, abandoning all idea of success with spherical shot, adopted the cylindrical form. His first trials were made in the summer of 1821. Hemispherical ends were adapted to cylindrical shot, but abandoned, it being found desirable so to dispose the weight as to give the greatest possible length to the shot; grooves of various dimensions were tried, and were found not to answer when narrow, but required to be wide enough to allow their sides to be exposed, from one end to the other, to a current of air blowing straight between them. In 1822, some further experiments were made at Woolwich, with grooved leaden shot fired from musket barrels, and with wooden shot from a 5^-inch howitzer, in which the shot, being received on targets, or in banks of earth, were in numerous instances found to have flown in the manner expected, i. e. point foremost. Similar trials with grooved leaden bullets from a plain barrel, were made in 1823, to the extent of several hundreds; and the balls, when well made, were always found to fly end foremost. Large wooden grooved shot were also fired from a 24-pounder, at Kinsale Fort, and on some occasions by night with lighted fusees in their sides, by which contrivance it was distinctly seen that the spiral motion was acquired and maintained steadily throughout their flight.

scholarly journals XXVII. On the long spectrum of electric light

1862 ◽  
Vol 152 ◽  
pp. 599-619 ◽  
Keyword(s):  
Solar Spectrum ◽  
Visible Spectrum ◽  
Stray Light ◽  
Copper Electrodes ◽  
Royal Institution ◽  
Direct Experiment ◽  
The Subject ◽  
Chain Of Evidence ◽  
Electric Light ◽  
Experimental Researches

The experimental researches described in a former paper led me indirectly to the con­clusion that the electric spark, whether obtained directly from the prime conductor of an ordinary electrifying machine, or from the discharge of a Leyden jar, emits rays of very high refrangibility, surpassing in this respect any that reach us from the sun—and that these rays pass freely through quartz, while glass absorbs them, as it does also the most refrangible of the solar rays. I was induced in consequence to procure prisms and a lens of quartz, which were applied in the first instance to the examination of the solar spectrum, and which immediately revealed the existence of an invisible region extending as far beyond that previously known as the latter extends beyond the visible spectrum, and exhibiting a continuation of Fraunhofer’s lines. A map of the new lines was exhibited at an evening lecture delivered before the British Association at their Meeting in Belfast in the autumn of the same year; and I then stated that I conceived we had obtained evidence that the limit of the solar spectrum in the more refrangible direction had been reached. In fact, the very same arrangement which revealed, by means of fluorescence, the existence of what were evidently rays of higher refrangibility coming from the electric spark failed to show anything of the kind when applied to the solar spectrum. At least, the only link in the chain of evidence which remained to be sup­plied by direct experiment related to the reflecting power, for rays of high refrangibility, of the metallic speculum of the heliostat which was employed to reflect the sun’s rays into a convenient direction; and this was shortly afterwards tested by direct experiment, on rays from an electric discharge separated by prismatic refraction. In making preparations for a lecture on the subject delivered at the Royal Institution in February 1853, in which I had the benefit of the kind assistance of Mr. Faraday, recourse was naturally had to electric light, on account of the extraordinary richness which it had been found to possess in rays of high refrangibility. Although fully pre­pared to expect rays of much higher refrangibility than were found in the solar spectrum, I was perfectly astonished, on subjecting a powerful discharge from a Leyden jar to prismatic analysis with quartz apparatus, to find a spectrum extending no less than six or eight times the length of the visible spectrum, and could not help at first suspecting that it was a mistake arising from the reflexion of stray light. A similarly extensive spectrum was obtained from the voltaic arc, and this was sufficiently bright to be exhi­bited to the audience, the arc passing between copper electrodes, and the pure spectrum formed by quartz apparatus being received on a piece of uranium glass cut for the pur­pose. The spectrum thus formed was found to consist entirely of bright lines, whereas the spectrum of the discharge of a Leyden jar had appeared (perhaps from not having been truly in focus) to be continuous, or at least not wholly discontinuous.

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.

scholarly journals XIV. On the absorption of gases by solids

1881 ◽  
Vol 32 (212-215) ◽  
pp. 407-408
Keyword(s):  
Royal Society ◽  
Hydraulic Press ◽  
Careful Examination ◽  
Solid Matter ◽  
Chemical Action ◽  
High Pressure And Temperature ◽  
Solid Iron ◽  
Series Of Experiments ◽  
The Subject ◽  
Very High

During the progress of the investigations which I have from time to time had the honour of bringing under the notice of the Royal Society, I have again and again noticed the apparent disappearance of gases inclosed in vessels of various materials when the disappearance could not be accounted for upon the assumption of ordinary leakage. After a careful examination of the subject I found that the solids absorbed or dissolved the gases, giving rise to a striking example of the fixation of a gas in a solid without chemical action. In carrying out that most troublesome investigation, the crystalline separation of carbon from its compounds, the tubes used for experiment have been in nine cases out of ten found to be empty on opening them, and in most cases a careful testing by hydraulic press showed no leakage. The gases seemed to go through the solid iron, although it was 2 inches thick. A series of experiments with various linings were tried. The tube was electro-plated with copper, silver, and gold, but with no greater success. Siliceous linings were tried fusible enamels and glass—but still the' tubes refused to hold the contents. Out of thirty-four experiments made since my last results were published, only four contained any liquid or condensed gaseous matter after the furnacing. I became convinced that the solid matter at the very high pressure and temperature used must be pervious to gases.

Discussion of “Methodology Used to Calculate Naval Compensated Gross Tonnage Factors” by John Craggs, Damien Bloor, Brian Tanner, and Hamish Bullen

2003 ◽  
Vol 19 (01) ◽  
pp. 29-30
Author(s):  
Thomas Lamb
Keyword(s):  
The Other ◽  
The Past ◽  
Royal Institution ◽  
Naval Ship ◽  
The Subject

I have been working in this area for the past 9 years. As the Craggs et al paper states, I have presented a number of papers on the subject (Lamb 1998, Lamb 2002, Lamb & Hellesoy 2001, Lamb & Knowles 1999, Storch et al 1995). The Craggs et al paper is the second publication I have seen by others about naval ship compensation coefficients. The other was Brian Tanner's paper presented at the Royal Institution of Naval Architects meeting last year describing how the British Ministry of Defence with First Marine International has been working on this matter for the past 2 years.

SOME MICROBIOLOGICAL STUDIES OF TWO SPECIES OF APHIDS, APHIS FABAE SCOP. AND MACROSIPHUM PISI (HARRIS) (HEMIPTERA, HOMOPTERA: APHIDIDAE)

1963 ◽  
Vol 9 (1) ◽  
pp. 65-73 ◽  
Author(s):  
N. N. LeBlanc ◽  
A. J. Musgrave
Keyword(s):  
Aphis Fabae ◽  
General Body ◽  
Histological Sections ◽  
Beneficial Microorganisms ◽  
Series Of Experiments ◽  
The Subject

Since 1850, aphids have been regarded as harboring, in mycetomes, supposedly beneficial microorganisms which have, however, been the subject of some controversy. In the present study of the aphids Aphis jabae and Macrosiphum pisi, mycetomes were identified in histological sections; but it proved impossible to isolate or culture any mycetomal microorganisms. Moreover, in a series of experiments in which great attention was paid to refined aseptic techniques no microorganisms could be isolated from the general body cavities or alimentary tracts of the aphids, though simultaneous attempts to isolate microorganisms from weevils were successful.

scholarly journals LXI. An account of the phænomena of elec­tricity in vacuo, with some observations thereupon

1752 ◽  
Vol 47 ◽  
pp. 362-376 ◽  
Keyword(s):  
Series Of Experiments ◽  
The Subject

Gentlemen, In a paper I had the honour to lay before you in January 1747, which was the last I communicated to you of my own upon the subject of electricity, and which has been since publish'd in the Philos. Trans , I acquainted you, that I intended upon some future occasion to lay before you a series of experiments in electricity made in vacuo ;

scholarly journals A Study on the Mainstream of Real Estate Education with Core Term Analysis

2018 ◽  
Vol 8 (4) ◽  
pp. 182
Author(s):  
Dong-hyun Kim ◽  
Myoung-young Pior
Keyword(s):  
United States ◽  
United Kingdom ◽  
Real Estate ◽  
The United States ◽  
Main Stream ◽  
The United Kingdom ◽  
Royal Institution ◽  
The Subject ◽  
Real Estate Education ◽  
Globalization Of Education

This study was conducted to provide basic information about the curricula of real estate education with respect to globalization. The literature, such as the histories and characteristics of real estate education in the United Kingdom and the United States that have historically lead real estate education, are reviewed. We also extract the core terms used in the curricula of departments accredited by the Royal Institution of Chartered Surveyors and The Association to Advance Collegiate Schools of Business—International that are leading the globalization of education, and Meikai University, the only university with a real estate department in Japan. In extracting core terms from each country, we proceed with basic terms that constitute the subject titles, not the entire subject title itself. After extracting core terms from each country, we discuss the overall characteristics of real estate education in each country and clarify the main stream of the globalization of real estate education. In addition, by comparing core terms and calculating proximities among Japan, the United Kingdom and United States, Japan’s specificities of real estate education are identified.

scholarly journals Studies in heredity. I.―The effects of crossing the sea-urchins echinus esculentus and echinocardium cordatum

1911 ◽  
Vol 84 (573) ◽  
pp. 394-403 ◽  
Keyword(s):  
Sea Water ◽  
Sea Urchins ◽  
Female Parent ◽  
Dilute Acid ◽  
Joint Paper ◽  
Echinocardium Cordatum ◽  
Normal Larva ◽  
Series Of Experiments ◽  
The Subject ◽  
The Cross

The manner in which parental characters are transmitted to the offspring when different species of Echinoderms are crossed has been the subject of much experimental enquiry and quite contradictory conclusions have been arrived at by different investigators. Thus Vernon (13), who carried out a most extensive series of experiments with the species of the genera Arbacia, Echinus, Strongylocentrotus, Sphærechinus, and Echinocardium which are available at Naples, came to the conclusion that the condition of the genital glands of the parents (whether imperfectly ripe, fully ripe, or stale) determines in many cases whether or not a hybrid will be formed, and further that though in the majority of cases the hybrid exhibits purely maternal characters, yet it sometimes exhibits paternal characters also, and that this result is also due to the condition of ripeness of the genital glands of its parents. Herbst (5), who also worked at Naples and who used the genera Echinus, Strongylocentrotus, and Sphærechinus for his experiments, found also that the hybrids in many cases showed the paternal influence, but that the extent to which this influence was exhibited varied with the temperature. Doncaster (1), who likewise worked at Naples, also arrived at the conclusion that the greater or less development of paternal characters in the hybrid was due to the temperature. On the other hand, Loeb (7, 8) and his pupil Hagedoorn (4) came to the conclusion that the hybrid exhibited purely maternal characters, and Fischel (2) arrived at the same conclusion on the whole. This conclusion is the more remarkable because Hagedoorn in his experiments used two species of the same genus. Tennent (12) crossed species of the American genera Toxopneustes and Hipponoe and found that the characters of Hipponoe were dominant in the hybrid whichever way the cross was made, but that if the alkalinity of the sea-water were reduced by the addition of dilute acid the influence of Toxopneustes became increased. Lastly Loeb, Redman King, and Moore in a joint paper published quite recently (9), in which they record the results of experiments with the same two species which Hagedoorn used, arrive at the conclusion that the exhibition of paternal and maternal characters in the hybrid is governed by the principle of Mendelian dominance, since, as they assert, the same characters appear in the hybrid whichever way the cross is made, whether, that is to say, in any particular case the character in question is inherited from the male or from the female parent. During a study of the whole subject which I recently made with the object of summarising the present state of our knowledge of this question of the inheritance of paternal and maternal characters in the hybrid, I was struck with the necessity of a preliminary thorough investigation of the characters of the normal larvæ of the species used in hybridisation experiments. The amount of general acquaintance with Echinoderm larvæ displayed by several of the investigators who have attacked the subject is, to say the least, somewhat defective. Thus Herbst (5), who studied chiefly the cross between Sphærechinus and Strongylocentrotus, attaches great importance to the extent to which lattice-work appears in the skeleton of the arms of the hybrid. In the normal larva of Strongylocentrotus, it is true, all four arms are supported by unbranched calcareous rods, whilst in the normal larva of Sphærechinus, each of the two posterior arms is supported by parallel rods connected by cross-pieces like the steps of a ladder, an arrangement which is termed “lattice-work.” But Herbst fails to take into account the fact that in the normal larva of Strongylocentrotus a lattice-work skeleton can appear as a variation, and hence an attempt such as he makes to estimate quantitatively the influence of one parent by the amount of lattice-work which appears in the hybrid rests upon an insecure foundation.

VI. Fifth letter on voltaic combinations, with some account of the effects of a large constant battery. Addressed to Michael Faraday, Esq. D. C. L. F. R. S., Fullerian Prof. Chem. Royal Institution, &c. &c. &c. By J. Frederic Daniell, Esq. F. R. S., Prof. Chem. in King's College, London

1839 ◽  
Vol 129 ◽  
pp. 89-95 ◽  
Keyword(s):  
Royal Society ◽  
Conducting Surface ◽  
Conducting Sphere ◽  
Active Point ◽  
King's College ◽  
Royal Institution ◽  
The Subject ◽  
Michael Faraday

My dear Faraday, In my last letter to you, which the Royal Society have done me the honour to publish in the Philosophical Transactions for 1838, I observed, that “the principal circumstance which might be supposed to limit the power of an active point within a conducting sphere, in any given electrolyte, is the resistance of that electrolyte, which increases in a certain ratio to its depth or thickness.” The superficial measure of the conducting sphere, and the distance of the generating metal, or the depth and resistance of the electrolyte, are, in fact, the variable conditions in a voltaic combination upon which its efficiency depends; and their relations require further investigation before we shall be able to determine what may be the proper proportions for the economical application of the power to useful purposes. I shall venture, therefore, to trouble you with the results of some further experiments upon the subject, and upon different combinations of the constant battery, before I proceed to communicate some observations upon Electrolysis, which I trust you will find not without interest, and to which, according to my plan, my attention has been lately exclusively directed. Looking, for a moment, upon the affinity which circulates in the battery as a radiant force, it seemed desirable to ascertain what would be the result of intercepting the rays by the conducting surface nearer to their centre than in the arrangements which have been previously described, as the relation of the generating and conducting metals to each other might be thereby more clearly ascertained.

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