Earl Grey Memorial Lecture1923 |
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Achaean Aegean alpha particle Argos ARMSTRONG COLLEGE NEWCASTLE-ON-TYNE Asia Minor Assyria atomic number atomic weight believe British called cathode century chemical chlorine civiliza civilization Cnossian Cnossus Cretan Crete cube Dalton's decoration democracy democratic representative government Dorian dynasty EARL GREY MEMORIAL electrical elements English fact foreign French gift of speech Greece Greek GREY MEMORIAL LECTURE helium Hellenism human hydrogen Iliad instance interest international contacts international understanding Ireland isotopes Italy language Late Minoan League of Nations Leleges mass means ments Minoan period Minos molecules motives Mycenae neon NEWCASTLE-ON-TYNE nuclear charge nucleus order lines OXFORD UNIVERSITY PRESS parabolas Parliament particles party Peloponnese personal liberty planetary electrons political pre-Achaean problem promote protons public opinion question radio-active rays relations remain Second Late Minoan Sparta statesmanship teachers theory things tion to-day trade transmutation true tumbler of water Twilight vases whole number rule whole numbers
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Stran 12 - It will be noticed- that the displacement to the right with increasing mass is roughly linear. The measurements of mass made are not absolute, but relative to lines which correspond to known masses. Such lines due to hydrogen, carbon, oxygen and their compounds are generally present as impurities or purposely added, for pure gases are not suitable for the smooth working of the discharge tube. The two principal groups of these reference lines are the...
Stran 14 - The first pair are second order lines and are fainter than the other two. All four are well placed for direct comparison with the standard lines, and a series of consistent measurements showed that to within about one part in a thousand the atomic weights of the isotopes composing neon are 20 and 22 respectively. Ten per cent, of the latter would bring the mean atomic weight to the accepted value of 20.20, and the relative intensity of the lines agrees well with this proportion.
Stran 19 - It has been said that the man who makes two blades of grass grow where there was but one before is a benefactor to mankind.
Stran 12 - F, and if a photographic plate is placed at GF as indicated, a spectrum dependent on mass alone will be obtained. On account of its analogy to optical apparatus, the instrument has been called a positive ray spectrograph and the spectrum produced a mass-spectrum.
Stran 12 - CO» line (44), a very good scale of reference. It must be remembered that the ratio of mass to charge is the real quantity measured by the position of the lines. Many of the particles are capable of carrying more than one charge. A particle carrying two charges will appear as having half its real mass, one carrying three charges as if its mass were one-third, and so on.
Stran 12 - A portion of this spectrum deflected through an angle 6 is selected by the diaphragm D and passed between the circular poles of a powerful electromagnet O the field of which is such as to bend the rays back again through an angle <f> more than twice as great as 0.
Stran 9 - This was that whereas all elements previously examined gave single, or apparently single, parabolas, that given by neon was definitely double. The brighter curve corresponded roughly to an atomic weight of 20, the fainter companion to one of 22, the atomic weight of neon being 20.20.
Stran 12 - It must be remembered that the ratio of mass to charge is the real quantity measured by the position of the lines. Many of the particles are capable of carrying more than one charge. A particle carrying two charges will appear as having half its real mass, one carrying three charges as if its mass was one-third, and so on. Lines due to these are called lines of the second and third order. Lines of high order are particularly valuable in extending our scale of reference. When neon was introduced into...
Stran 17 - By far the most important result of these measurements is that, with the exception of hydrogen, the weights of the atoms of all the elements measured, and therefore almost certainly of all elements, are whole numbers to the accuracy of experiment, namely, about one part in a thousand Of course, the error expressed in fractions of a unit increases with the weight measured, but with the lighter elements the divergence from the whole-number rule is extremely small.
Stran 6 - It is an admirable formula ; but it presupposes not only that public opinion exists, but that on any particular question there is a public opinion ready to decide the issue. Indeed, it presupposes that the supreme statesman in democratic government is public opinion. Many of the shortcomings of democratic government are due to the fact that public opinion is not necessarily a great statesman at all.