scholarly journals XXXIX. Continuation of an experimental inquiry concerning the nature of the mineral elastic spirit, or air, contained in the Pouhon water, and other aciculæ

1774 ◽  
Vol 64 ◽  
pp. 357-371

Sir, You have often, with others of my friends, been pleased to inquire after the continuation of my experiments on the mineral water of spa, which I promised to communicate to the Royal Society, with a view to explain "the mode of union that exists between the "air of those waters, and the other principles of "which they are composed, together with the "relation which that elastic fluid bears to common "air, and to various other bodies ( a )."

1853 ◽  
Vol 143 ◽  
pp. 357-365 ◽  

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.


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.


Author(s):  
Derek Hull

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’.


1809 ◽  
Vol 99 ◽  
pp. 146-147

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.


1832 ◽  
Vol 122 ◽  
pp. 539-574 ◽  

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.


1868 ◽  
Vol 16 ◽  
pp. 254-258

The results of my researches on the chloroform-derivatives of the primary monamines, which, as I have shown, are isomeric with the nitriles, could not fail to direct my attention to allied groups of bodies, with the view of discovering similar isomerisms. In a note communicated to the Royal Society some months ago, I expressed the expectations which even then appeared to be justified in the following manner:—“In conclusion, I may be permitted to announce as everv probable the existence of a series of bodies isomeric with the sulphocyanides. Already M. Cloëz has shown that the action of chloride of cyanogen on ethylate of potassium gives rise to the formation of an ethylic cyanate possessing properties absolutely different from those belonging to the cyanate discovered by M. Wurtz. On comparing, on the other hand the properties of the methylic and ethylic sulphocyamdes with those of the sulphocyanides of allyl and phenyl, it can scarcely be doubted that we have here the representatives of two groups entirely different, and that the terms of the methyl- and ethyl-series which correspond to oil of mustard, and to the sulphocyanide of phenyl, still remain to be discovered. Experiments with which I am now engaged will show whether these bodies cannot be obtained by the action of the iodides of methyl and ethyl on sulphocyanide of silver."


The first record for Thursday, 27 October 1743,is an isolated entry written on a sheet of paper pasted on the inside cover of Minute Book No. 1; it lists the names of eight Members who each paid six shillings for the month to Mr Colebrook, the Treasurer, for four dinners to be ordered at i/6d.per head. The Treasurer had to order each Thursday ‘a dinner for six and pay nine shillings certain’ to the innkeeper of the Mitre Tavern in Fleet Street; ‘as many more as come to pay one-and-sixpence per head each’ but if more than six come, ‘the deficiency to be paid out of this Fund of -£2.8.0.’, the amount he had received that day. O f these eight men six were Fellows of the Royal Society and the other two became Fellows later.


On 4 March 1660—61 ‘glass bubbles’ were first introduced to a meeting of the Royal Society. According to the minutes, ‘The King sent by Sir Paul Neile five little glass bubbles, two with liquor in them, and the other three solid, in order to have the judgement of the society concerning them’ (1). The Royal Society responded with remarkable celerity: its amanuensis produced some more drops two days later, which ‘succeeded in the same manner with those sent by the king’ (2). A very full report of the experiments performed was given to the Royal Society on 14 August 1661 by the President, Sir Robert Moray (3). As the Royal Society did not at this time have a normal publication series the report was recorded in the Register Book (4) and first published by Merret as an appendix to his translation of Neri’s Art of Glass (5). Henry Oldenburg lent Sir Robert’s account to the French traveller Monconys in 1663 who made his own translation into French of the prescription for making the drops. Monconys published this prescription in the second part of his Voyages (6). The ‘bubbles’— the solid ones, at least— were what were later to be called ‘Prince Rupert’s drops’. (Those said to contain ‘liquor’ could have been something different, but were probably the same containing vacuoles and no actual liquid.) These objects, glass beads with the form of a tear-drop tapering to a fine tail, made (though that was not generally known at the time) by dripping molten glass into cold water, exhibited a paradoxical combination of strength and fragility not without interest to the materials scientist of the present day, and which could not fail to excite the imagination of natural (and not so natural) philosphers of the 17th century. The head withstands hammering on an anvil, or, as a more modern test, squeezing in a vice, indenting its steel jaws, without fracture: yet breaking the tail with finger pressure caused the whole to explode into powder.


The type of deformation under investigation is indicated by fig. 1. A rectangular plate ABCD is deformed into the shape A'B'C'D'. The two opposing edges AB, CD are shifted horizontally without alteration of length into the position A'B', C'D', the other boundaries AD, BC being kept free from external stress. In a paper which appeared in the 'Proc. Royal Society', December 28, 1911, Prof. E. G. Coker investigated this same type of deformation using optical methods to determine the distribution of stress along the centre line OX. He found that if the plate was square the shear stress along OX was distributed in a munner which was approximately parabolic. As the ratio of AD to AB decreased the curve of distribution first of all became flat-topped, and for yet smaller ratios two distinct humps made their appearance.


1695 ◽  
Vol 19 (234) ◽  
pp. 738-740 ◽  
Keyword(s):  

I Have had pretty good Hap in adding to my Roman Curiosities, Two entire Urns, both of the Blewish Grey Clay, but different Forms, with some of the burnt Bones, and Two other Vessels of the Red Clay the letter of them is almost in the Form of the Roman Simpulum or Guttus .


Sign in / Sign up

Export Citation Format

Share Document