2026-10-08 Google Search (Chrome), then DuckDuckGo and WebSearch as fallback

Google queries (in order): 1. "Lorentz" archief Noord-Hollands Archief inventaris "Lorentz" Hendrik Antoon correspondence led to NHA archive 364 (see the NHA note). Other hits: an NHA overview of science archives (PDF); a KNAW DWC biography (dwc.knaw.nl/berkelbio/34.lorentz.pdf); Kox and Schatz's biography A Living Work of Art: The Life and Science of Hendrik Antoon Lorentz; the Cambridge chapter on H. Johanna van Leeuwen (cites "Lorentz Archive, Inventaris nr. 752-754, Noord-Hollands Archief"); Leiden thesis chapter "Chapter V: Lorentz" (scholarlypublications.universiteitleiden.nl), on Teylers Museum. 2. Lorentz lectures Columbia University 1906 "Ernest Kempton Adams" OR "Spectator" electrons led to the Columbia Spectator (see its note). Also: the book is Publication No. 2 of the Ernest Kempton Adams Fund for Physical Research. The Adams fund was set up on 17 December 1904 by Edward Dean Adams; Planck's Eight Lectures (1909) is in the same series. Wikipedia's "Ernest Kempton Adams Lectures" lists "1906-07: Hendrik Lorentz". There is a Wikimedia Commons PDF of the 1909 edition [web, search snippets]. 3. Lorentz 1927 "Conference on the Michelson-Morley experiment" Astrophysical Journal 1928 Lorentz remarks local time gave ApJ 68 (1928) 341-390/402 (Mount Wilson, 4-5 Feb 1927; participants Michelson, Lorentz, D. C. Miller, R. J. Kennedy, E. R. Hedrick, P. S. Epstein). Also G. Holton, "Einstein, Michelson, and the 'Crucial' Experiment" (1969), Harvard DASH PDF [web, snippets]. 4. neo-Lorentzian relativity preferred frame Builder Prokhovnik Jánossy Ives "Lorentz ether theory" physical contraction gave Wikipedia LET; Bischoff van Heemskerck 2024 (PMC11318248; see the misc note); Grokipedia "Neo-Lorentzian Relativity" (AI-written, secondary); and Ekkehard Friebe's chronology of critical publications, which lists "1980 - Clube, S. V. M.: Does neo-lorentzian relativity exist?" [web, snippets]. 5. Lorentz letter Einstein aether "Lorentz to Einstein" 1915 OR 1916 OR 1919 einsteinpapers.press.princeton.edu gave CPAE (Collected Papers of Albert Einstein) citations: Einstein to Lorentz 12 Oct 1915 (CPAE 8, Doc. 129); Lorentz to Einstein 1 Jan 1916 (CPAE 8, Doc. 177); Lorentz to Einstein before 23 Jan 1915 (Kox 2008, p.278, quoted in A Living Work of Art); Einstein to Lorentz 22 Feb 1921 and Lorentz to Einstein 19 Mar 1921 (CPAE 12, Docs. 57 and later) [web, snippets]. Not opened. 6. dwc.knaw.nl Lorentz "Electromagnetic phenomena in a system moving with any velocity smaller than that of light" pdf found the KNAW Digital Library PDF https://dwc.knaw.nl/DL/publications/PU00014148.pdf. A header check (curl -I) gave HTTP 200, application/pdf, 982,745 bytes. Not downloaded. This is Lorentz's 1904 paper, the source of §§169-178 [web]. 7. Brace 1904 "double refraction" "motion through the ether" Philosophical Magazine Rayleigh 1902 repetition found: M. Janssen and J. Stachel, "The Optics and Electrodynamics of Moving Bodies" (PDF via d-nb.info); R. McCormmach, "H. A. Lorentz and the Electromagnetic View of Nature" (Isis 1970, JSTOR); the Springer "Frontiers of Physics: 1900-1911" chapter ("Abraham's theory predicted a double refraction well within the limits of accuracy of Rayleigh and Brace"); Brace, "On Double Refraction in Matter Moving through the Aether", Phil. Mag. [web, snippets]. 8. Jánossy "Theory of relativity based on physical reality" Lorentz ether contraction physical OR Prokhovnik "Logic of special relativity" found: L. Jánossy, Theory of Relativity Based on Physical Reality (Akadémiai Kiadó, Budapest 1971); S. J. Prokhovnik, The Logic of Special Relativity (Cambridge UP 1967); M. Arminjon's scalar ether theory of gravitation papers (arXiv 2011; Found. Phys. 2004; HAL 1998); J. F. Barrett, "The hyperbolic theory of special relativity" (arXiv 2011) [web, snippets]. 9. Kox "Scientific Correspondence of H.A. Lorentz" volume 2 Theory of Electrons second edition 1916 Columbia was blocked by a Google "unusual traffic" CAPTCHA page, about 6 minutes in. Not solved. Search moved to DuckDuckGo.

DuckDuckGo (html) queries: - Kox "Scientific Correspondence of H.A. Lorentz" volume 2 found Kox (ed.), The Scientific Correspondence of H.A. Lorentz, vol. I (Springer 2008, 434 letters out of about 6,000 that survive) and vol. 2, The Dutch Correspondents (Springer 2018, 294 letters, including Zeeman and Ehrenfest). The GBV table of contents PDF was fetched; it lists only the front matter. - review Lorentz "Theory of Electrons" 1909 OR 1916 Nature OR Science "second edition" was blocked by a DuckDuckGo image CAPTCHA. Not solved.

WebSearch (fallback after both CAPTCHAs): - Zahn Spees 1938 "critical analysis of the classical experiments on the variation of electron mass" Bucherer Neumann found: the APS issue listing (Phys. Rev. 53, no. 7) gives the title "A Critical Analysis of the Classical Experiments on the Relativistic Variation of Electron Mass"; J. Potters, "Hazy Spots on Photographic Plates" (PhilSci 22988); Einstein Papers vol. 2 docs 306 and 308 [web]. - Lorentz "The Theory of Electrons" review 1909 Nature OR "Physical Review" OR Science book review Columbia lectures found: E. B. Wilson's review of the 2nd edition, Bull. AMS 24 (1917) 100-101 (https://www.ams.org/journals/bull/1917-24-02/S0002-9904-1917-03025-X); A. J. Kox, "H.A. Lorentz, Lectures on electron theory, First edition (1909)", in Grattan-Guinness (ed.), Landmark Writings in Western Mathematics 1640-1940 (Elsevier 2005), pp.778-783 (https://dare.uva.nl/id/5e78aafb-f04e-44b2-980d-cd9aa34ff281) [web].