RankingsPrimerArbiterPhysicistMathematicianContrarianQESites logClaimsSourcesResearch notes

2026-10-09 Wikisource

Pages: Author:Ernest_Rutherford; Popular Science Monthly/Volume 67/May 1905/Present Problems in Radioactivity (saved: research/pages/wikisource-psm67-present-problems.html and .txt); 1911 Encyclopaedia Britannica/Radioactivity (saved: research/pages/wikisource-eb1911-radioactivity.html).

  1. Present Problems in Radioactivity (St Louis address, Sept 1904; PSM 67, May 1905) [web: https://en.wikisource.org/wiki/Popular_Science_Monthly/Volume_67/May_1905/Present_Problems_in_Radioactivity] - Two views stated: "Some have considered that the atoms of the radio-elements act as transformers of borrowed energy. The atoms are supposed, in some way, to abstract energy from the surrounding medium..." versus energy "derived from the radio-atoms themselves". - "There is no direct evidence in support of the view that the energy of the radio-elements is derived from external sources, while there is much indirect evidence against it." - "Some sort of chemical theory is thus required to explain the facts whether the view is taken that the energy is derived from the atom itself or from external sources." - Against the external theory: "It certainly can not be from the air itself, for radium gives out heat inside an ice calorimeter. It can not be any type of rays such as the radioactive bodies emit, for the radioactivity of radium, and consequently its heating effect is unaltered by hermetically sealing it in a vessel of lead several inches thick." "Unless there is some unknown source of energy in the medium which the radioactive bodies are capable of absorbing..." - Detonator: "The experimental results are equally in agreement with the view that each atom contains within itself the potentiality of its final disruption, or with the view that the disintegration is precipitated by the action of some external cause ... in the same way that a detonator is necessary to start certain explosions. The energy set free is, however, not derived from the detonator, but from the substance on which it acts." - Emanation energy: about 10,000 gram calories from the emanation of 1 g radium; about three million times the energy of an equal volume of hydrogen burning. - Ordinary matter: "all the matter that has so far been examined shows undoubted traces of radioactivity, but it is very difficult to show that the radioactivity observed is not due to a minute trace of known radioactive matter"; reports J. J. Thomson's British Association account of evidence for specific radioactivity of ordinary matter. - Rate independence: emanation constant "unaffected between the limits of temperature of 450 C and -180 C". Bears on: claims 2 and 7 (and the Le Bon quotation; compare the French original, 2026-10-09-archive-org.md).

  2. EB1911 "Radioactivity" (Rutherford, initials "E. Ru.") [web: https://en.wikisource.org/wiki/1911_Encyclop%C3%A6dia_Britannica/Radioactivity]: states the evolution of heat by radium is "mainly a secondary phenomenon, resulting mainly from the expulsion of a particles"; emanation volume about 0.6 cubic mm per gram of radium. No detonator or external-energy passage found by grep.

  3. Author page: lists Radio-activity (1905) transcription project, EB1911 and EB1926 ("Matter", "Radioactivity") articles, DNB 1927 article on Moseley, early NZ Institute papers (1894-95). Result: positive.