Atoms and rays : an introduction to modern views on atomic structure & radiation / by Sir Oliver Lodge.

  • Oliver Lodge
Date:
1924
Catalogue details

Licence: In copyright

Credit: Atoms and rays : an introduction to modern views on atomic structure & radiation / by Sir Oliver Lodge. Source: Wellcome Collection.

    19/220 (page 13)
    x3 i] Chemical Affinity about which less is known, each of which is called a proton. An atom of matter is really built up of equal numbers of these opposite particles; so that an atom can be analysed, and proved to consist of an aggregate of electrons and pro¬ tons, grouped together according to certain well-defined and ascertainable laws. Hence the ultimate atom, or apparently indivisible particle, is now no longer the atom of matter, as had been thought, but is the atom of electricity; and of electricity all the atoms are made. All that was previously discovered about the size of atoms, and the way they combine into molecules by elec¬ trical forces, and the way these molecules either hang together under cohesive forces to form the solids and liquids that we know, or fly about in a fairly free manner almost devoid of cohesion in what we call the gaseous state—all this remains true; though with some modifications, because the effective size of atoms, now that each is known to be a group or system, is perceived to be rather indefinite and dependent on circumstances. The rarer and cooler and purer the gas, the bigger may be the group that constitutes an atom; for alien and violent collisions may ionise it. But apart from that, and in addition to all this knowledge, the intimate constitution of the atoms themselves is now being revealed to us. Sun and Planets in Miniature Atoms are extremely, almost inconceivably, small; and yet they consist of parts which are millions of times smaller. And recently it has been found, and almost if not completely proved, that the atoms are constructed somewhat on the basis of a solar system; that is to say, that they have at the centre a massive nucleus consisting mainly of an aggregate of protons, with a definite number of electrons circulating round the nucleus, very much as the planets revolve round the sun. And furthermore, that the particles themselves are so small that their distances apart inside the atom are