The Scientific Proceedings of the Royal Dublin Society, Bind 11Royal Dublin Society, 1908 |
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acid aperture appear atmometer calcium cent cerium chloride condensation cornea crystalline crystalline lens dew-point diameter didymium dilution distance Dublin Element and Intensity entoptic object entoptic observation entoptic phenomena Entoptiscope evaporation experiments fall of temperature glass Globigerina Ooze GOLD ELECTRODES gold lines grams per gram hydrochloric acid inch increase lanthanum length lens light liquid ment metal method millimetre molecules muscæ open cup oxyhydrogen flame paper photograph pin-hole Pipe Plate pressure Proc projected image pupil QUANTITATIVE SPECTRUM quantity radium Radium in grams rays RAYS-continued Received for Publication relative humidity residuary lines retina Roan Royal Dublin Society saturated SCIENT screen seen shadow spectra strong solution substance surface TABLE teetotum thallium tube vapour-pressure vapour-tension vessels water-surface wave-lengths yellow spot yttrium
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Side 79 - WOLLASTON'S method is exceedingly accurate. When I look at a minute lucid point, such as the image of a candle in a small concave speculum, it appears as a radiated star, as a cross, or as an unequal line, and never as a perfect point, unless I apply a concave lens inclined at a proper angle, to correct the unequal refraction of my eye.
Side 133 - ... control, but beyond our knowledge. If it be true that the conception of a regular geometrical pattern implies the exercise of thought and intelligence, it would almost seem that in such cases as those above adduced we have evidence of a thought, an intelligence, working within our own organization distinct from that of our own personality.
Side 174 - Thus both ordinary and eledrical evaporation are more rapid in a vacuum than at the ordinary atmospheric pressure. I have recently made some experiments upon the evaporation of different substances under the electric stress. Evaporation of Water. — A delicate balance was taken, and two very shallow porcelain dishes were filled with acidulated water and balanced on the pans. Dipping into each dish — touching the liquid but not the dish— was a platinum wire, one connected with the induction coil...
Side 105 - ... sulphur, the reaction between copper and mercuric chloride, and between potassium nitrate and sodium acetate. The formation of the sulphide of copper, and other sulphides, was accomplished by Mr. Spring by compression of the elements. But it is not even necessary that the sulphur and copper be in contact. I have made the sulphide at ordinary temperatures with the two an inch apart and a wad of cotton in the tube between them.
Side 72 - ... utilitarian character ; and this is but one of numerous proofs which the progress of knowledge is daily accumulating, that the most abstract and apparently transcendental truths in physical science, will sooner or later, add their tribute to supply human wants, and alleviate human sufferings. Nor has science performed one of the least important of her functions, when she enables us either in our own case or in that of others, to dispel those anxieties and fears which are the necessary offspring...
Side 174 - ... surrounding air, the excursions of the molecules of the liquid are rendered longer and the force of impact greater, and thus the escape of molecules into the upper region of gas is increased, and we say that evaporation is augmented. If the initial velocities of the liquid molecules can be increased by any other means than by raising the temperature, so that their escape into the gas is rendered more rapid, the result may be called " evaporation " just as well as if heat had been applied.
Side 216 - ... and all the lines disappear more rapidly; the last lines to disappear on dilution are identical with those observed by Hartley. That graphite should be more delicate than gold appears very natural, as the graphite tends to absorb the solution-sparks over a larger surface, and hence yields more vapor of the element under examination; but for all ordinary analytical purposes, gold is more convenient. The work was done with a one-prism quartz spectrograph, by Hilger, using the spark produced by...
Side 19 - ... lead to the con1 Tyndall's Contributions to Molecular Physics in the Domain of Radiant Heat. elusion that this anticipation in regard to the opacity of aqueous vapor is justified. But it has been contested by Magnus, who found the effect of dry air to be precisely the same as that of moist air, and " that the water present in the atmosphere at 16° C. exercises no perceptible influence on the radiation.
Side 228 - After sparking the strong solutions, it was found that in many cases the electrodes alone gave quite strong spectra of the metal under examination, and at first it was supposed that the solutions had sprayed on to the fresh electrodes ; but on keeping the fresh electrodes in another room, no difference was observed, and in the case of an element such as iron or calcium, the dilution spectra could not be followed beyond the -1 per cent, solution,, as the electrodes then gave as strong spectra as the...
Side 125 - ... bled to observe an appearance of luminous lines, branched and somewhat connected with each other, darting from every point of the field of view towards a centre a little exterior and superior to the axis of the eye. This centre corresponds to the insertion of the optic nerve, and the appearance of the line...