5. On a Constant Pressure Gas Thermometer

1880 ◽  
Vol 10 ◽  
pp. 539-545
Author(s):  
William Thomson
Keyword(s):  
Physical Properties ◽  
Royal Society ◽  
Constant Pressure ◽  
Steam Pressure ◽  
Thermal Capacity ◽  
Porous Plug ◽  
Proper Form ◽  
The Absolute ◽  
Important Object ◽  
Thermodynamic Scale

In the article on “Heat” published in the eleventh volume of the Encyclopœdia Britannica, referred to in my previous communications to the Royal Society on Steam Pressure Thermometers, it is shown that the Constant Pressure Air Thermometer is the proper form of expansional thermometer to give temperature on the absolute thermodynamic scale, with no other data as to physical properties of the fluid than the thermal effect which it experiences in being forced through a porous plug, as in the experiment of Joule and myself on this subject; and the thermal capacity of the fluid under constant pressure. These data for air, hydrogen, and nitrogen have all been obtained with considerable accuracy, and thererfore it becomes an important object towards promoting accurate thermometry, to make a practical working thermometer directly adapted to show temperature on the absolute thermodynamic scale through the whole range of temperature, from the lowest attainable by any means, to the highest for which glass remains solid.

scholarly journals VI. On the corrosion of copper sheeting by sea water, and on methods of preventing this effect ; and on their application to ships of war and other ships

1824 ◽  
Vol 114 ◽  
pp. 151-158 ◽  
Keyword(s):  
Experimental Investigation ◽  
Royal Society ◽  
Sea Water ◽  
Pure Copper ◽  
Chemical Science ◽  
Rapid Decay ◽  
Practical Applications ◽  
The Absolute ◽  
Important Object

1. The rapid decay of the copper sheeting of His Majesty's ships of war, and the uncertainty of the time of its duration, have long attracted the attention of those persons most con­cerned in the naval interests of the country. Having had my enquiries directed to this important object by the Com­missioners of the Navy Board, and a Committee of the Royal Society having been appointed to consider of it, I entered into an experimental investigation of the causes of the action of sea water upon copper. In pursuing this investigation, I have ascertained many facts which I think not unworthy of the notice of the Royal Society, as they promise to illustrate some obscure parts of electro-chemical science ; and likewise seem to offer important practical applications. 2. It has been generally supposed that sea water had little or no action on pure copper, and that the rapid decay of the copper on certain ships was owing to its impurity. On trying, however, the action of sea water upon two specimens of copper, sent by John Vivian, Esq. to Mr. Faraday for analysis, I found the specimen which appeared absolutely pure, was acted upon even more rapidly than the specimen which con­tained alloy : and, on pursuing the enquiry with specimens of various kinds of copper which had been collected by the Navy Board, and sent to the Royal Society, and some of which had been considered as remarkable for their durability, and others for their rapid decay, I found that they offered very inconsiderable differences only in their action upon sea water ; and, consequently, that the changes they had under­gone must have depended upon other causes than the absolute quality of the metal.

scholarly journals XIV. On the thermal effects of fluids in motion

1853 ◽  
Vol 143 ◽  
pp. 357-365 ◽  
Keyword(s):  
Royal Society ◽  
Mechanical Energy ◽  
Thermal Capacity ◽  
The Other ◽  
Porous Plug ◽  
Log P ◽  
Pressure Side ◽  
Conducting Material ◽  
Elastic Fluid ◽  
Mechanical Equivalent

In a paper communicated to the Royal Society, June 20, 1844, “On the Changes of Temperature produced by the Rarefaction and Condensation of Air,” Mr. Joule pointed out the dynamical cause of the principal phenomena, and described the experiments upon which his conclusions were founded. Subsequently Professor Thomson pointed out that the accordance discovered in that investigation between the work spent and the mechanical equivalent of the heat evolved in the compression of air may be only approximate, and in a paper communicated to the Royal Society of Edinburgh in April 1851, “On a Method of discovering experimentally the relation between the Mechanical Work spent, and the Heat produced by the compression of a Gaseous Fluid,” proposed the method of experimenting adopted in the present investigation, by means of which we have already arrived at partial results. This method consists in forcing the compressed elastic fluid through a mass of porous non-conducting material, and observing the consequent change of temperature in the elastic fluid. The porous plug was adopted instead of a single orifice, in order that the work done by the expanding fluid may be immediately spent in friction, without any appreciable portion of it being even temporarily employed to generate ordinary vis viva , or being devoted to produce sound. The non-conducting material was chosen to diminish as much as possible all loss of thermal effect by conduction, either from the air on one side to the air on the other side of the plug, or between the plug and the surrounding matter. A principal object of the researches is to determine the value of μ , Carnot’s function. If the gas fulfilled perfectly the laws of compression and expansion ordinarily assumed, we should have 1/ μ = 1/E + t /J + Kδ/E p 0 u 0 log P, where J is the mechanical equivalent of the thermal unit; p 0 u 0 the product of the pressure in pounds on the square foot into the volume in cubic feet of a pound of the gas at 0° Cent.; P is the ratio of the pressure on the high pressure side to that on the other side of the plug; δ is the observed cooling effect; t the temperature Cent, of the bath, and K the thermal capacity of a pound of the gas under constant pressure equal to that on the low pressure side of the gas. To establish this equa­tion it is only necessary to remark that Kδ is the heat that would have to be added to each pound of the exit stream of air, to bring it to the temperature of the bath, and is the same (according to the general principle of mechanical energy) as would have to be added to it in passing through the plug, to make it leave the plug with its temperature unaltered. We have therefore Kδ=—H, in terms of the notation used in the passage referred to.

scholarly journals Observed Relations Between Physical Properties and MK Classification as Functions of Metal Abundance for F5-K4 Stars

1976 ◽  
Vol 72 ◽  
pp. 75-78
Author(s):  
M. Grenon
Keyword(s):  
Physical Properties ◽  
Spectral Range ◽  
Spectral Type ◽  
Photometric System ◽  
Luminosity Class ◽  
Empirical Relations ◽  
Metal Abundance ◽  
Systematic Effects ◽  
The Absolute ◽  
Absolute Magnitudes

The Geneva photometric system has been calibrated in terms of [M/H], θeff, Mv in the spectral range F5 to K4. As the spectral type is a datum generally available, we derive empirical relations showing the coupling of θeff and [M/H] at given spectral type and luminosity class. Similar relations are offered for the absolute magnitudes and provide a more accurate means for deriving spectroscopic parallaxes. Systematic effects on the estimation of the luminosity class are also shown.

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.

XIV. Researches into the molecular constitution of the organic bases

1851 ◽  
Vol 141 ◽  
pp. 357-398 ◽  
Keyword(s):  
Physical Properties ◽  
Royal Society ◽  
General Outline ◽  
Organic Bases ◽  
History Of ◽  
The Subject ◽  
Molecular Constitution

About twelve months ago I had the honour of presenting to the Royal Society an account of a series of researches into the molecular constitution of the volatile organic bases: at present I beg to submit to the consideration of the Society the history of a new group of alkaloids, which, although intimately connected with the former by their origin, differ from them altogether by their properties, and especially in not being volatile . The members of this new group of alkaloids are so numerous, their deportment is so singular, and their derivatives ramify in so many directions, that I have not as yet been able to complete the study of these substances in all their bearings; nor is it my intention to go fully into the chemistry of the subject in the present com­munication, my object being merely to establish the existence of these bodies, and to give a general outline of their connection with the volatile bases, and of their most prominent chemical and physical properties, reserving a detailed description of their salts and derivatives to a future memoir.

scholarly journals The growth of the Fellowship

1938 ◽  
Vol 1 (1) ◽  
pp. 40-48
Keyword(s):  
Special Interest ◽  
Royal Society ◽  
The State ◽  
Printing Press ◽  
The Past ◽  
The Absolute

Unlike the Academies of Science in most other countries where they exist, the Royal Society is not restricted by the terms of its Charters in the number of candidates which may be admitted to the Fellowship. The selection and election of candidates is left to the absolute discretion of the President, Council and Fellows of the Society. The manner in which they have carried out this duty in the past is of special interest in studying the growth of the Society. From its foundation the Society was absolutely dependent upon its own resources, for it had neither a subvention from the State nor were its publications printed by an official printing press, advantages which other national academies have usually enjoyed. The subscriptions of its Fellows and occasional gifts and bequests were all that the Council could look to for meeting the growing expenses of the young Society. The development of an adequate membership was therefore imperative, and long engaged the Councils attention.

scholarly journals VIII.—Note as to the Dynamical Equivalent of Temperature in Liquid Water, and the Specific Heat of Atmospheric Air and Steam, being a Supplement to a Paper On the Mechanical Action of Heat

1853 ◽  
Vol 20 (2) ◽  
pp. 191-193
Author(s):  
William John Macquorn Rankine
Keyword(s):  
Cast Iron ◽  
Specific Heat ◽  
Liquid Water ◽  
Royal Society ◽  
Constant Pressure ◽  
Mechanical Action ◽  
Numerical Results ◽  
Detailed Account ◽  
Atmospheric Air ◽  
Apparent Specific Heat

(33*.) In my paper on the Mechanical Action of Heat, published in the 1st Part of the 20th Volume of the Transactions of the Royal Society of Edinburgh, some of the numerical results depend upon the dynamical equivalent of a degree of temperature in liquid water. The value of that quantity which I then used, was calculated from the experiments of De la Roche and Bérard on the apparent specific heat of atmospheric air under constant pressure, as compared with liquid water.The experiments of Mr Joule on the production of heat by friction, give, for the specific heat of liquid water, an equivalent about one-ninth part greater than that which is determined from those of De la Roche and Bérard. I was formerly disposed to ascribe this discrepancy in a great measure to the smallness of the differences of temperature measured by Mr Joule, and to unknown causes of loss of power in his apparatus, such as the production of sound and of electricity; but, subsequently to the publication of my paper, I have seen the detailed account of Mr Joule's last experiments in the Philosophical Transactions for 1850, which has convinced me, that the uncertainty arising from the smallness of the elevations of temperature, is removed by the multitude of experiments (being forty on water, fifty on mercury, and twenty on cast iron); that the agreement amongst the results from substances so different, shews that the error by unknown losses of power is insensible, or nearly so; and that the necessary conclusion is, that the dynamical value assigned by Mr Joule to the specific heat of liquid water, viz.:—772 feet per degree of Fahrenheit, does not err by more than two or at the utmost, three feet; and therefore, that the discrepancy originates chiefly in the experiments of De la Roche and Bérard.

scholarly journals II. Physical properties of nickel steel

1890 ◽  
Vol 47 (286-291) ◽  
pp. 138-139 ◽  
Keyword(s):  
Magnetic Properties ◽  
Physical Properties ◽  
Royal Society ◽  
Nickel Steel ◽  
Steel Company ◽  
The Wire

Mr. Riley, of the Steel Company of Scotland, has kindly sent me samples of wire drawn from the material concerning the magnetic properties of which I recently made a communication to the Royal Society. As already stated, this material contains 25 per cent, of nickel and about 74 per cent, of iron, and over a range of temperature from something below freezing to 580º C. it can exist in two states, magnetic and non-magnetic. The wire as sent to me was magnetisable as tested by means of a magnet in the ordinary way. On heating it to a dull redness it became non-magnetisable whether it was cooled slowly or exceedingly rapidly by plunging it into water.

scholarly journals VIII.—The Electrical Resistance of Nickel at High Temperatures

1887 ◽  
Vol 33 (1) ◽  
pp. 187-198
Author(s):  
Cargill G. Knott
Keyword(s):  
Thermal Expansion ◽  
High Temperature ◽  
Electrical Resistance ◽  
Royal Society ◽  
Thermal Capacity ◽  
Short Paper ◽  
Electric Conductor ◽  
Physical Laboratory ◽  
University Of Edinburgh ◽  
The University

In the Proceedings of the Royal Society of Edinburgh for 1874–75 there is a short paper on the “Electrical Resistance of Iron at a High Temperature.” It is the record of certain experiments made by three of us, then students in the Physical Laboratory of the University of Edinburgh; and its conclusion is that there is a peculiarity in the behaviour of iron as an electric conductor at the temperature of a dull red heat. At this temperature other physical peculiarities are known to exist, particularly as regards its thermal expansion, its thermal capacity, and its specific heat for electricity. The discovery of these striking properties we owe respectively to Dr Gore, Professor Barrett, and Professor Tait.

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