XIII. Experimental researches in voltaic electricity and electro-magnetism

1832 ◽  
Vol 122 ◽  
pp. 279-298 ◽  
Keyword(s):  
Experimental Investigation ◽  
Royal Society ◽  
Physical Science ◽  
The Subject ◽  
Experimental Researches ◽  
Made In

The splendid discoveries which have lately been made in magnetism and electro-magnetism have so much engaged the attention of philosophers, that the theory and laws of action of voltaic electricity, no longer possessing the charms of novelty, have been entirely neglected. The subject appearing to me full of interest, and lying at the very foundation of a large portion of physical science, induced me to undertake an experimental investigation of some of the most important points connected with it, the result of which I have the honour of laying before the Royal Society.

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.

scholarly journals XIII. On the laws of polarisation and double refraction in regularly crystallized bodies. By David Brewster, LL. D. F. R. S. Lond. and Edin. In a letter to the Right Hon. Sir Joseph Banks, Bart. G. C. B. P. R. S

1818 ◽  
Vol 108 ◽  
pp. 199-273 ◽  
Keyword(s):  
Present State ◽  
General Principle ◽  
Royal Society ◽  
Physical Science ◽  
Double Refraction ◽  
General Law ◽  
Relative Value ◽  
Combined Action ◽  
The Subject ◽  
The Right

Dear sir, In the different memoirs which you have done me the honour of submitting to the Royal Society, I have considered principally those branches of the polarisation of light which relate to the superficial action, or the superinduced properties of uncrystallized bodies. In the course of these enquiries, my attention was frequently directed to the phenomena of regular crystals; but from the difficulty of procuring proper specimens, and the extreme perplexity of the subject, it was not till lately that I succeeded in reducing under a general principle all the complex appearances which result from the combined action of more than one axis of double refraction. Before I proceed to trace the steps which have conducted me to this general law, I must entreat the indulgence of the Society, while I attempt to give a brief and rapid view of the present state of our knowledge respecting the laws of double refraction. They will thus be able to appreciate more correctly the relative value of those successive generalisations by which this subject has been raised to one of the most interesting departments of physical science.

XIX. On the immediate principles of human excrements in the healthy state

1857 ◽  
Vol 147 ◽  
pp. 403-413 ◽  
Keyword(s):  
Royal Society ◽  
Physical Science ◽  
Alcoholic Solution ◽  
Healthy State ◽  
The Subject

In June 1854 I had the honour of communicating to the Royal Society an account of some investigations I had undertaken respecting the composition of the excrements of man and animals; since that time I have continued my researches on human excrements, and obtained further results which form the subject of the present paper. I have been most ably seconded in this work by my assistant, Mr. Frederick Dupré, Ph. D., and have derived much valuable aid from his thorough knowledge of chemical and physical science. The method of investigation employed in this instance is similar to that which had been adopted on the former occasion; alcohol and ether were again the principal means employed for conducting the analysis, chemical decompositions being thereby avoided and the constituents of excrements consequently obtained under the form of Immediate Principles . It will also be observed that in this case, for the purpose of extracting excretine, the alcoholic solution of excrements was in many instances not mixed with milk of lime, which simplified materially the operations and increased the interest of the investigation.

scholarly journals III. Experimental researches in electricity. —eighteenth series

1843 ◽  
Vol 133 ◽  
pp. 17-32 ◽  
Keyword(s):  
High Pressure ◽  
Royal Society ◽  
Atmospheric Electricity ◽  
Glass Tube ◽  
Direct Relation ◽  
High Pressure Steam ◽  
Change Of State ◽  
Pressure Steam ◽  
The Subject ◽  
Experimental Researches

2075. Two years ago an experiment was described by Mr. Armstrong and others, in which the issue of a stream of high pressure steam into the air produced abundance of electricity. The source of the electricity was not ascertained, but was supposed to be the evaporation or change of state of the water, and to have a direct relation to atmospheric electricity. I have at various times since May of last year been working upon the subject, and though I perceive Mr. Armstrong has, in recent communi­cations, anticipated by publication some of the facts which I also have obtained, the Royal Society may still perhaps think a compressed account of my results and con­clusions, which include many other important points, worthy its attention. 2076. The apparatus I· have used was not competent to furnish me with much steam or a high pressure, but I found it sufficient for my purpose, which was the in­vestigation of the effect and its cause, and not necessarily an increase of the electric development. Mr. Armstrong, as is shown by a recent paper, has well effected the latter. The boiler I used, belonging to the London Institution, would hold about ten gallons of water, and allow the evaporation of five gallons. A pipe 4½ feet long was attached to it, at the end of which was a large stop-cock and a metal globe, of the capacity of thirty-two cubic inches, which I will call the steam-globe , and to this globe, by its mouth-piece, could be attached various forms of apparatus, serving as vents for the issuing steam. Thus a cock could be connected with the steam-globe, and this cock be used as the experimental steam-passage; or a wooden tube could be screwed in; or a small metal or glass tube put through a good cork, and the cork screwed in; and in these cases the steam way of the globe and tube leading to the boiler was so large, that they might be considered as part of the boiler, and these terminal passages as the obstacles which, restraining the issue of steam, produced any important degree of friction.

On the Natural Occurrence of Herpetomonads (Leptomonads) in Mice

Parasitology ◽  
1915 ◽  
Vol 8 (1) ◽  
pp. 128-132 ◽  
Author(s):  
H. B. Fantham ◽  
Annie Porter
Keyword(s):  
Peripheral Blood ◽  
Natural Occurrence ◽  
Relapsing Fever ◽  
Camera Lucida ◽  
Laboratory Assistant ◽  
The Subject ◽  
Experimental Researches ◽  
Made In

While engaged in experimental researches on the introduction of insect flagellates, belonging to the genera Herpetomonas and Crithidia, into vertebrates, we have recalled to mind some former observations of ours made in 1909. When examining the blood of mice artificially infected with the spirochaetes of relapsing fever in the Quick Laboratory, Cambridge, we observed flagellates in the peripheral blood of the mice. These flagellates, which were scanty, were studied in fresh preparations by us and drawings of the organism were made with the camera lucida. Some of these drawings are now reproduced, together with others made by us subsequently. The flagellates were also observed by Professor Nuttall and his laboratory assistant, Mr B. G. Clarke, and we were unanimously agreed that the flagellates belonged to the genus Herpetomonas, or Leptomonas as some have since preferred to call it. The significance of the presence of herpetomonads in the blood of mice was very puzzling at the time, and pressure of other work prevented the subject being followed up. During 1911 and 1912, these flagellate organisms have been seen by all of us, but they were always evanescent and could not be found in fixed and stained preparations. The parasites were seen on different occasions in three mice altogether.

XXIX. On the tides of Bombay and Kurrachee

1868 ◽  
Vol 158 ◽  
pp. 685-696 ◽  
Keyword(s):  
Royal Society ◽  
Diurnal Tide ◽  
Semidiurnal Tide ◽  
Royal Observatory ◽  
The Subject ◽  
Engineering Survey ◽  
Continuous Curves ◽  
Made In

The tides on the coasts of India present a marked difference from those on our own coasts in the large amount of diurnal inequality to which they are subject. My attention was first directed to the subject in the course of an engineering survey of the Harbour of Kurrachee which I made in 1857-58, when I obtained between three and four months’ continuous observations, a copy of which is deposited with the Royal Society. Subsequently I obtained from the Admiralty, through the kindness of Captain Burdwood, R. N., the loan of the records of three years’ observations taken at Bombay in 1846, 1847, and 1848. Of these I plotted in a series of continuous curves the records for 1846, and deposited them, at the Astronomer Royal’s request, at the Royal Observatory, Greenwich. These records, however, are not perfect. They were made by a self-acting machine, the adjustment of which does not appear to have been always accurately pre­served; and I hope that they will be superseded as data for investigation by a better record 'for the year 1868. Taking them as they were, however, I discussed them to obtain the semimonthly curves of semidiurnal tide, and also formulæ for the approxi­mate determination of diurnal tide.

scholarly journals VI. Additional note to the eleventh series of researches on the tides

1840 ◽  
Vol 130 ◽  
pp. 161-174 ◽  
Keyword(s):  
Royal Society ◽  
Great Care ◽  
Additional Note ◽  
The Subject ◽  
Made In ◽  
Remarkable Manner

The tide observations which I recorded and discussed in my eleventh memoir on that subject, were laid before the Royal Society, because, though the different series of observations were both brief and imperfect, the features of the tide phenomena as there exhibited were novel; and it appeared desirable to put them on record with a view to future comparison with other places. I have now to notice other observations which I have received from another region, and which display similar features in a still more remarkable manner. These, with the results of a few other sets of observations, which may, I trust, hereafter be of use, I beg to lay before the Society, as an Appendix to my eleventh memoir on the subject of the Tides. The principal tide observations which I now bring forward are those for which I am indebted to the Russian Admiral Lὒtke. These observations were made in 1827 and 1828 by the officers and men of the Seniavine corvette, commanded by the (then) Captain Lütke. From the account given me of the mode of observing, it appears that they were made with proper apparatus and with great care and perseverance, as is indeed sufficiently shown by the observations themselves. At one place (Petro-paulofsk in Kamtchatka) the height of the surface was carefully observed every ten minutes day and night; and when near its maximum, every two minutes. And it is proper to remark, that this great care and labour, which would have been superfluous at most places, was necessary in this instance. If the observations had not been thus continued, they would not have enabled us to detect the very curious laws of the phenomena which I have now to describe.

scholarly journals V. Experimental researches on the functions of the mucous membrane of the gall-bladder, principally with reference to the conversion of Hepatic into Cystic bile

1857 ◽  
Vol 8 ◽  
pp. 133-140
Keyword(s):  
Gall Bladder ◽  
Physical Properties ◽  
Mucous Membrane ◽  
Royal Society ◽  
Hepatic Bile ◽  
Pathological Conditions ◽  
Mucous Membranes ◽  
The Subject ◽  
Experimental Researches ◽  
Chemical Experiment

Referring to the well-known difference in taste and other physical properties between the bile as it immediately proceeds from the liver and the same fluid after it has been retained for a time in the gallbladder, the author observes, that the nature of this difference and the agency by which it is effected, are questions which have not yet met with the attention they deserve, and that he had accordingly been led to make them the subject of experimental inquiry. As, however, it is only on rare occasions that the hepatic bile can he procured in quantity sufficient for chemical experiment, and then only at the risk of its being altered by pathological conditions of the secreting organ, the author considers that, however clearly individual facts on the subject may be demonstrated, any deductions made therefrom must be referred to the lower department of probable evidence; and it is with this reservation that he lays his conclusions before the Royal Society, whilst, at the same time, he believes that, so far as the nature of the case admits, he has been able to elicit a new fact respecting the mucous membrane of the gallbladder, which may lead to the better comprehension of the functions of mucous membranes generally.

VII. On a group of varieties of the muscles of the human neck, shoulder, and chest, with their transitional forms and homologies in the mammalia

1870 ◽  
Vol 160 ◽  
pp. 83-116 ◽  
Keyword(s):  
Head And Neck ◽  
Royal Society ◽  
King's College ◽  
Extensive Range ◽  
Statistical Frequency ◽  
The Subject ◽  
Transitional Forms ◽  
Made In

In the 'Proceedings of the Royal Society,’ between the years 1864 and 1868 inclusive, were published five series of observations upon variations in Human Myology, made in the Anatomical Rooms of King’s College, London. These observations extended over 202 dissected subjects ; they were restricted chiefly to the muscles of the head and neck and those acting upon the extremities, and did not include the numerous irregularities which are usually found in those of the back. From the extensive range of the subject, and the importance of ascertaining as far as possible the statistical frequency of the abnormal forms, there was little opportunity afforded of giving due prominence to many of the specimens which were entitled to special distinction, either from their first appearance in the records of anatomical science, or from their homological importance as transitional forms, or as representatives of muscles hitherto found only in certain classes of animals.

I. On the electromotive properties of the leaf of dionæa in the excited and unexcited states

1882 ◽  
Vol 33 (216-219) ◽  
pp. 148-151
Keyword(s):  
Royal Society ◽  
Lower Layer ◽  
Electric Properties ◽  
Cylindrical Cell ◽  
Mechanical Excitation ◽  
Du Bois ◽  
The Subject ◽  
Experimental Researches

The paper consists of five parts. Part I is occupied by the examination of two experimental researches, relating to the subject, which have been published in Germany since the date of the anthor’s first communication to the Royal Society in 1873, namely, that of Professor Munk on Dionæa, and of Dr. Kunkel on electromotive action in the living organs of plants. According to Dr. Munk, the electric properties of the leaf may be explained on the theory that each cylindrical cell of its parenchyma is an electromotor, of which the middle is, in the unexcited state, negative to the ends, and that on excitation the electromotive forces of the cells of the upper layer undergo diminution, those of the lower layer an increase. He accounts for the diphasic character of the electrical disturbance which follows mechanical excitation by attributing it to the opposite electromotive reactions of the two layers of cells. According to this theory, the cells resemble in their properties the “electromotive muscle-molecules” (“Unter-suchungen,” vol. i, p. 682, 1848, of du Bois Reymond) differing from them in so far that their poles are positive instead of being negative to their equatorial zones. Professor Munk has constructed a schematic leaf in which the cells are represented by zinc cylinders with copper zones. A schema so made is said by him to have the electromotive properties of the unexcited leaf. Dr. Kunkel’s experiments have for their purpose to show that all the electromotive phenomena of plants may be explained as consequences of the movement of water in the organs at the surfaces of which they manifest themselves.

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