London and Edinburgh Philosophical Magazine and Journal of Science, 1849, Vol. 35 (Classic Reprint)


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Excerpt from London and Edinburgh Philosophical Magazine and Journal of Science, 1849, Vol. 35 The inorganic constituents of vegetable and animal substances have received more attention during the last few fears than was formerly the case; and in consequence of Liebig's exertions especially, numerous investigations of the ashes of organic substances' have been made; but their principal object was only technical. It was soon perceived, that as plants derive the inorganic constituents, without which they cannot exist, from the soil, it was of the greatest importance to determine these constituents with accuracy, so as to be enabled to judge whether the soil was capable of yielding them; and if not so, to allow of their being added in the form of a suitable manure. Hitherto almost all these investigations have been directed to the determination of the relative proportions of the inorganic constituents of the ash. Occasionally, indeed, the presence of certain inorganic constituents, especially salts, has been detected by microscopic examinations; but scarcely any one has expressly taken up the question which is somewhat closely connected with this point, viz. in what manner are the inorganic substances combined with the organic? Whether they form with each other the same kinds of combinations as those which are artificially prepared in our laboratories, or whether peculiar compounds, existing only in living organic bodies, are formed by the mutual influence of the inorganic upon the organic matters, are questions which must be of great importance, especially in animal and vegetable physiology, and which have not hitherto been accurately investigated. In very few instances only have researches of this kind been attempted. About the Publisher Forgotten Books publishes hundreds of thousands of rare and classic books. Find more at www.forgottenbooks.com This book is a reproduction of an important historical work. Forgotten Books uses state-of-the-art technology to digitally reconstruct the work, preserving the original format whilst repairing imperfections present in the aged copy. In rare cases, an imperfection in the original, such as a blemish or missing page, may be replicated in our edition. We do, however, repair the vast majority of imperfections successfully; any imperfections that remain are intentionally left to preserve the state of such historical works.




The London, Edinburgh, and Dublin Philosophical Magazine and Journal of Science, Vol. 35


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Excerpt from The London, Edinburgh, and Dublin Philosophical Magazine and Journal of Science, Vol. 35: January-June, 1893 If hard glass be employed instead of porcelain, then there is insecurity in the joints between it and the glass used for the remainder of the apparatus. Metal tubes present similar difficulties with regard to the junctions, and are besides more or less porous at high temperatures. Another grave dis advantage is that, whether porcelain or glass tubes be used, there is always a chance of a crack occurring, and perhaps escaping notice. The reduction of the copper also presents great difficulty it is more difficult to get a strong stream of really pure hydrogen or carbon monoxide than to get the nitrogen; and any sulphur absorbed by the copper is a permanent disadvantage; for, as metallurgists know, copper contain ing sulphur may be oxidized and reduced many times and yet at each oxidation some sulphur will burn out. The reason is, of course, that sulphide of copper heated in air forms some sulphate of copper as well as sulphur dioxide. On the next reduction sulphide of copper is re-formed, and then, on passing air over the mixture, the process of incom plete oxidation is repeated. Judging by a discussion which took place in Section A of the British Association not long ago, these simple facts are not as widely known as might have been expected. I know of no reagent which will absorb sulphur dioxide so as to form an absolutely stable compound, and which is itself easy to prepare in a state of sufficient purity to be above suspicion of giving off foreign matters to the nitrogen. Of course it may he argued that a large number of vessels containing, say, a solution of caustic potash might be used, the second retaining the sulphur dioxide given off from the first, and so 011; but this device is obviously unsuited for a continuous process, where the reagents must be untouched for weeks or months. About the Publisher Forgotten Books publishes hundreds of thousands of rare and classic books. Find more at www.forgottenbooks.com This book is a reproduction of an important historical work. Forgotten Books uses state-of-the-art technology to digitally reconstruct the work, preserving the original format whilst repairing imperfections present in the aged copy. In rare cases, an imperfection in the original, such as a blemish or missing page, may be replicated in our edition. We do, however, repair the vast majority of imperfections successfully; any imperfections that remain are intentionally left to preserve the state of such historical works.




The London, Edinburgh, and Dublin Philosophical Magazine and Journal of Science, Vol. 19


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Excerpt from The London, Edinburgh, and Dublin Philosophical Magazine and Journal of Science, Vol. 19: January-June, 1860 The instrument consists of a glass tube, ab, in serted in a light half-pint ask A, the connexion at e 1) being made air-tight 3 a thermometrical scale m n attached to the tube 3 a moveable barometrical scale C I) 3 Q a piece of very thin india-rubber tied over the top of the tube A B, to keep the external air from coming in contact with the strong sulphuric acid occupying a portion of the tube and ask. The tube AB is about 24 inches long, and about gths of an inch internal diameter; it is secured to the ask in the following manner z - Two perforated corks, e and fitting the neck of the ask, are placed on the tube the lower one, e, is coated with a solution of india-rubber to render it impervious to air; the upper cork, '0, being raised a little, the cork c with the tube is pressed down to its proper depth some pieces of chemical cement, fusible at a gentle heat, are now placed above the cork e, and a gentle heat is applied until the cement melts the upper cork v is then brought down to its place upon the melted cement when the cement has cooled, the tube will be found firmly fixed in the ask and perfectly air-tight. Strong sulphuric acid of commerce is introduced through the tube by means of a pipette, the tube being held in an inclined position. N.b. All this process of cementing may be obviated by having a globe and tube bent in the manner shown in the succeeding diagram but I preferred Showing how the instrument may be constructed cheaply, and with materials which may be readily obtained. About the Publisher Forgotten Books publishes hundreds of thousands of rare and classic books. Find more at www.forgottenbooks.com This book is a reproduction of an important historical work. Forgotten Books uses state-of-the-art technology to digitally reconstruct the work, preserving the original format whilst repairing imperfections present in the aged copy. In rare cases, an imperfection in the original, such as a blemish or missing page, may be replicated in our edition. We do, however, repair the vast majority of imperfections successfully; any imperfections that remain are intentionally left to preserve the state of such historical works."




The London, Edinburgh, and Dublin Philosophical Magazine and Journal of Science, Vol. 3


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Excerpt from The London, Edinburgh, and Dublin Philosophical Magazine and Journal of Science, Vol. 3: January-June, 1877 I have generally In my remarks adopted a chronological arrangement of the various researches, because it is only thus that the course Of thought which I have followed can be logically represented. A systematic arrangement would, it is true, place the Simpler before the more complex conditions but in the present case the latter, which occur chiefly in the case of luminous carbon-containing flames, are the more im portant and have been more studied. The experience gained from the study of flames burning under complex conditions is tested and applied in the case of simpler flames, and so becomes a guide to the explanation of the conditions affecting luminous flames in general. Diminution and Restoration of Luminosity in Hydrocarbon flames. About the Publisher Forgotten Books publishes hundreds of thousands of rare and classic books. Find more at www.forgottenbooks.com This book is a reproduction of an important historical work. Forgotten Books uses state-of-the-art technology to digitally reconstruct the work, preserving the original format whilst repairing imperfections present in the aged copy. In rare cases, an imperfection in the original, such as a blemish or missing page, may be replicated in our edition. We do, however, repair the vast majority of imperfections successfully; any imperfections that remain are intentionally left to preserve the state of such historical works.




The London, Edinburgh, and Dublin Philosophical Magazine and Journal of Science, Vol. 15


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Excerpt from The London, Edinburgh, and Dublin Philosophical Magazine and Journal of Science, Vol. 15: January-June, 1883 The result Of the above - mentioned memoir, SO far as it regards the subject Of the present, may be summed up as follows -if 7' is the Obstacle to the propagation Of electricity which is Situated at the point Of passage between the elec trodes and the gas, the electric - resistance in a column Of gas Of unit length, and l the distance between the electrodes, 7°]7°1l will be the sum Of the resistance which the electricity must overcome in order to pass from one electrode to the other. Of these values, r increases continually in proportion as the gas is rarefied, while during the same time undergoes incessant diminution. From a judicious interpretation Of the experiments which have been made, especially those Of Hit torf, it follows that the augmentation Of the first Of these quantities and the diminution Of the other continued until the gas had arrived at the greatest rarefaction it was possible to Obtain by means Of the mercury pump employed. In the space exhausted Of air, r acquires such a value that it is im possible for the current to surmount it. If, then, the current cannot traverse a vacuum, it is not because the value T1 of the resistance has become too great, but because r is augmented to such a degree that the current is incapable Of surmounting it. Several properties Of gases with respect to the passage Of electricity show that this interpretation Of the resistance which the Oppose to its propagation is really the only true one. About the Publisher Forgotten Books publishes hundreds of thousands of rare and classic books. Find more at www.forgottenbooks.com This book is a reproduction of an important historical work. Forgotten Books uses state-of-the-art technology to digitally reconstruct the work, preserving the original format whilst repairing imperfections present in the aged copy. In rare cases, an imperfection in the original, such as a blemish or missing page, may be replicated in our edition. We do, however, repair the vast majority of imperfections successfully; any imperfections that remain are intentionally left to preserve the state of such historical works.




The London, Edinburgh, and Dublin Philosophical Magazine and Journal of Science, Vol. 3


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Excerpt from The London, Edinburgh, and Dublin Philosophical Magazine and Journal of Science, Vol. 3: Fourth Series; January-June, 1852 Sir D. Brewster on the Development and Extinction of regular doubly-refracting Structures in the Crystalline Lenses of Ani mals after Death. (with a Plate.) Mr. M. Donovan on the supposed Identity of the Agent con cerned in the Phaenomena of ordinary Electricity, Voltaic Electricity, Electro Magnetism Magneto-electricity, and Thermo electricity (continued) About the Publisher Forgotten Books publishes hundreds of thousands of rare and classic books. Find more at www.forgottenbooks.com This book is a reproduction of an important historical work. Forgotten Books uses state-of-the-art technology to digitally reconstruct the work, preserving the original format whilst repairing imperfections present in the aged copy. In rare cases, an imperfection in the original, such as a blemish or missing page, may be replicated in our edition. We do, however, repair the vast majority of imperfections successfully; any imperfections that remain are intentionally left to preserve the state of such historical works.




The London, Edinburgh, and Dublin Philosophical Magazine and Journal of Science, Vol. 36


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Excerpt from The London, Edinburgh, and Dublin Philosophical Magazine and Journal of Science, Vol. 36: July-December, 1868 The grand simplicity of the idea of the conservation of force, together with the tendency to generalize which influences most inquirers in scientific matters, would naturally lead to the belief that if mechanical energy is directly convertible into heat, heat should be also directly convertible into mechanical energy, and, of course, in the same proportion. Hence it is assumed that when a hot perfect gas performs work by expansion in a cylinder supposed to be neutral to the thermometric effects of heat, and having a piston moving without friction, it must naturally lose as much heat in raising a weight of 7 72 pounds one foot as would raise the temperature of one pound of liquid water 1 de gree of Fahrenheit's scale. By the same reasoning, steam, in performing work in vessels supposed to be equally neutral to heat, should lose exactly the same quantity of heat in doing the same quantity of work; and as perfect steam (neither super heated nor containing water in suspension) cannot lose heat without undergoing a corresponding amount of condensation, it is assumed that in the working of the steam-engine as much steam is condensed (theoretically) as corresponds to the amount of work performed in the proportion of Joule's equivalent, and consequently that the quantitative heat of the steam passing into the condenser is by so much less than the total heat of the steam furnished by the boiler to the engine. More than thirty years ago Seguin, in his interesting work On the Influence of Railways, ' endeavoured to trace the dyna mical relation which he saw must exist between the heat applied to the boiler and. The energy developed by the engine; and it is remarkable that, in many experiments made by him on the actual working of steam-engines, with the express purpose of proving the disappearance of quantitative heat which he thought must be converted into the work done, he could not detect the expected disappearance of heat. About the Publisher Forgotten Books publishes hundreds of thousands of rare and classic books. Find more at www.forgottenbooks.com This book is a reproduction of an important historical work. Forgotten Books uses state-of-the-art technology to digitally reconstruct the work, preserving the original format whilst repairing imperfections present in the aged copy. In rare cases, an imperfection in the original, such as a blemish or missing page, may be replicated in our edition. We do, however, repair the vast majority of imperfections successfully; any imperfections that remain are intentionally left to preserve the state of such historical works.




The London, Edinburgh, and Dublin Philosophical Magazine and Journal of Science, Vol. 25


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Excerpt from The London, Edinburgh, and Dublin Philosophical Magazine and Journal of Science, Vol. 25: Fifth Series; January-June, 1888 Mr. W. E. Sumpner on the Variation of the Coefficients of Induction. (plate III.) Profs. W. E. Ayrton and J. Perry on the Efficiency Of Incandescent Lamps with Direct and Alternating Currents Mr. E. C. Rimington on the Measurement of the Power sup plied to the Primary Coil of a Transformer Dr. C. H. Draper on the Polarization of Platinum Plates. Profs. W. E. Ayrton and J. Perry on the Magnetic Circuit of Dynamo Machines. (plate Mr. H. F. N ewall on the Recalescence of Steel. Mr. J. Parker on an Extension of Carnot's Theorem Notices respecting New Books Transactions of the Edinburgh Geological Society, Vol. V., Part III. About the Publisher Forgotten Books publishes hundreds of thousands of rare and classic books. Find more at www.forgottenbooks.com This book is a reproduction of an important historical work. Forgotten Books uses state-of-the-art technology to digitally reconstruct the work, preserving the original format whilst repairing imperfections present in the aged copy. In rare cases, an imperfection in the original, such as a blemish or missing page, may be replicated in our edition. We do, however, repair the vast majority of imperfections successfully; any imperfections that remain are intentionally left to preserve the state of such historical works.




The London, Edinburgh and Dublin Philosophical Magazine and Journal of Science, Vol. 20


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Excerpt from The London, Edinburgh and Dublin Philosophical Magazine and Journal of Science, Vol. 20: July December, 1860 Between the two black surfaces 1 and 2 Of equal temperature, imagine a body placed which may refract, re ect, and absorb the rays which pass between them in any way whatever. Several pencils may reach surface 2 from surface 1 3 of these let one be chosen, and let that part Of it be taken when it leaves 1, which consists Of waves Of length between X and d7x, and let this be divided into two component parts polarized at right angles to each other in the planes a1 and 61. Let that part of the first component which reaches 2 be itself divided into two parts, whose planes Of polarization are the perpendicular but otherwise arbitrary planes a2, Let the intensity of the part polarized in aq be d. Of the pencil which pursues the same path, but in the Opposite direction, viz. From 2 to 1, consider at 2 the part which consists Of the waves whose length lies between 7t and X]d7t, and let it again be divided into two parts polarized in the planes ac, and [22, and let the portion of the first component part that reaches 1 be also divided into two components polarized in a1 and Let the intensity Of the part polarized in al be K' Then k=ki. About the Publisher Forgotten Books publishes hundreds of thousands of rare and classic books. Find more at www.forgottenbooks.com This book is a reproduction of an important historical work. Forgotten Books uses state-of-the-art technology to digitally reconstruct the work, preserving the original format whilst repairing imperfections present in the aged copy. In rare cases, an imperfection in the original, such as a blemish or missing page, may be replicated in our edition. We do, however, repair the vast majority of imperfections successfully; any imperfections that remain are intentionally left to preserve the state of such historical works."




The London, Edinburgh, and Dublin Philosophical Magazine and Journal of Science, Vol. 25


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Excerpt from The London, Edinburgh, and Dublin Philosophical Magazine and Journal of Science, Vol. 25: January June, 1863 1. For eighteen years it has pressed on my mind, that essential principles of thermo-dynamics have been overlooked by those geologists who uncompromisingly oppose all paroxysmal hypotheses, and maintain not only that we have examples now before us, on the earth, of all the different actions by which its crust has been modified in geological history, but that these actions have never, or have not on the whole, been more violent in past time than they are at present. 2. It is quite certain the solar system cannot have gone on, even as at present, for a few hundred thousand or a few million years without the irrevocable loss (by dissipation, not by annihilation) of a very considerable proportion of the entire energy initially in store for sun heat, and for plutonic action. It is quite certain that the whole store of energy in the solar system has been greater in all past time than at present; but it is conceivable that the rate at which it has been drawn upon and dissipated, whether by solar radiation, or by volcanic action in the earth or other dark bodies of the system, may have been nearly equable, or may even have been less rapid, in certain periods of the past. But it is far more probable that the secular rate of dissipation has been in some direct proportion to the total amount of energy in store, at any time after the commencement of the present order of things, and has been therefore very slowly diminishing from age to age. About the Publisher Forgotten Books publishes hundreds of thousands of rare and classic books. Find more at www.forgottenbooks.com This book is a reproduction of an important historical work. Forgotten Books uses state-of-the-art technology to digitally reconstruct the work, preserving the original format whilst repairing imperfections present in the aged copy. In rare cases, an imperfection in the original, such as a blemish or missing page, may be replicated in our edition. We do, however, repair the vast majority of imperfections successfully; any imperfections that remain are intentionally left to preserve the state of such historical works.