The Scientific Proceedings of the Royal Dublin Society, Volume 9Royal Dublin Society, 1902 |
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absorbent absorption acid alkaline ammonia amount of atmospheric amount of carbonic analysis anatase Annalen Annales de Chimie apparatus Assay Plan atmospheric carbonic anhydride augite baryta baryta solution baryta water Berichte Biedermann's Centrbl bottle carbonic acid carbonique cent Chem chemical clock CO₂ colour containing crystals cubic centimetres curve D.Sc dilute Dissolved oxygen Dublin Soc Duplicate dyke effect error felspar gases glass glucoside ground air H₂O heat Hofmann's Jahresber hydrate hydrochloric acid Joly Journ Kohlensäuregehalt l'air latter light liquid litre Luft mean melting point method metres minerals mixture Müntz nitrogen O. P. Compt observed obtained occur ordinary orthoclase oxide paper Pettenkofer's Plate porphyritic potash pressure Proc Professor quantity quartz Received for Publication river rock Royal Dublin Society salt sample Science sewage silica Silurian SIR HOWARD GRUBB soluble substance supersaturated surface temperature tion titrated Traces tube Ueber vessel volume Wollny's Forsch Zeitschr
Popular passages
Page 84 - ... to the number of molecules that are present may seem very indefinite ; but it is far from being valueless. succeed in measuring are the distances of those few stars which have perceptible parallax *. The distances of these stars from the Solar System range from four to fifteen metro-six teens ; and it is not likely that any star could send us light enough to be visible in any of our telescopes if a thousand times more remote. At a distance, then, of about ten thousand metrosixteens — that is,...
Page 92 - Inthis way of measuring time 300 metres of time (1000 feet*) is the same as the millionth of one second. OF MOLECULAR EVENTS. In molecular physics the periods of time which have to be dealt with are almost inconceivably shorter than any to which we are accustomed. The unit of time which the present writer has found the most generally convenient is the micron of time — the time which light takes to advance one micron forward in the open aether.
Page 82 - ... of chemical atoms in each cubic millimetre of solids and liquids — not exactly that number, but somewhere near it. He thus arrived at an estimate — an estimate, not a determination — as to the number of molecules in a gas, and as to the number of chemical atoms in solids and liquids. Such knowledge is imperfect, but is much better than knowing nothing about the scale on which Nature is working in this branch of her operations. The general results of the information acquired in 1860 were...
Page 85 - The survey may be rendered definite with the help of the table comprised in fig. 6, in which numerical digits are to take the place of some of the ciphers. According to the place where we insert these numbers we can make them express by how many metres, or by what fraction of a metre, we are to measure any of the magnitudes with which man has become acquainted throughout the whole range of his study of Nature. In this table metres mean decimal multiples of the metre ; metrets mean its decimal sub-multiples...
Page 85 - IP, from millims (millimetres) down to tenths of a micron, covers the entire ranye of the microscope, and indeed travels somewhat beyond the grasp of that instrument, since the smallest interval at which two objects can be seen as two by the best immersion objectives supplemented by the best immersion condensers, and most carefully handled, is but little less than two tenths of a micron, which is the 127,000th of an inch ; whereas sub-section Cir extends twice as far, ie down to one tenth of a micron....
Page 397 - Centesimalgrade ändern kann. Hält man nun die schon nicht weniger als 400 bis 500 Atmosphären betragende Pressung, welche ungefähr zur Sprengung der 3 Millimeter dicken Wandung einer 2 Millimeter weiten Glasröhre erfordert wird, mit jener gewaltigen Druckkraft zusammen, welche die Feste ganzer Continente erschüttert oder emporhebt, und sich in meilenlangen...
Page 397 - Gesteine je nach dem Wechsel des Drucks ihre Erstarrungstemperatur um Hunderte von Graden ändern können. Man begreift daher leicht, dass Feldspath, Glimmer, Hornblende, Augit, Olivin etc., welche unter einem bestimmten Druck bei einer gewissen Temperatur aus dem silicatischen Lösungsmittel erstarren, unter verändertem Druck bei ganz andern Temperaturen auskrystallisiren werden.
Page 397 - Reihenfolge der Ausscheidungen, ja es werden sich diese Ausscheidungen selbst, ihrer chemischen Constitution nach, durch den blossen Druck ändern können. " Man wird es daher als ausgemacht betrachten dürfen, dass der Druck auf das Festwerden der plutonischen Gebirge und auf die chemische Constitution der darin auftretenden...
Page 99 - a barbarous country, where chemical spirits were so misunderstood, and chemical instruments so unprocurable, that it was hard to have any Hermetic thoughts in it ; " and he had betaken himself to " anatomical dissections " as the only kind of scientific pastime that Irish conditions favoured.
Page 88 - Bu, the sub-section of large planetary measures, indicates the place in our table in which to record the distances of the planets from the Sun, or from one another, as is seen from fig. 2. These distances are most conveniently read out as so many metro-tens. The next sub-section...