Mendeleev-D · Source catalogue

Longmans, Green 1904 English translation of Mendeleev's essay (printed pp.1-51, PDF pp.9-59), from the Cornell University Library copy scanned by the Internet Archive (archive.org/details/cu31924012371096). It has no preface or headings. Mendeleev argues that the ether should be treated as a chemical element, the lightest inert gas, and places it in a new 'zero series' of the periodic system above a new 'zero group' of noble gases (argon group), with a second unknown element y (possibly coronium) between the ether and hydrogen. He recalls his 1874 work with Kirpichev (spelled 'Kirpitchnikoff'/'Kirpichnikov' in the English text) on departures from Boyle's law at low pressure, and argues that the ether must have weight (citing Lord Kelvin's lower bound of about 1e-16 g per cubic metre) and must permeate all bodies as hydrogen permeates palladium. He estimates atomic weights of y (at most 0.4 from the Li:H ratio of 6.97) and x (at most 0.17 from noble-gas ratios, then far smaller from kinetic limits). The kinetic argument uses the root-mean-square (rms) molecular speed v = 1843 sqrt(2(1+at)/x) m/s (the mean speed is 1694 m/s), with space temperature taken as -80 degC, and compares with escape velocities of Earth (about 11.2 km/s), Sun (about 608 km/s) and heavy stars (up to 50 solar masses, about 2,240 km/s). He adopts for x an atomic weight near one millionth of hydrogen and a velocity of about 2,250 km/s. He cites radioactivity (a Curie flask demonstration of zinc sulphide fluorescing when joined to a radioactive solution) and Dewar's low-temperature phosphorescence as support, calls it 'a series of thoughts' and a hypothesis (PDF p.39), and says its object is to bring the question to the fore. PDF pp.61-100 are a Longmans publisher's catalogue ('A Select List of Books', not part of the essay); pp.8, 60 and 101-104 are blank. This copy (the deep-read reference copy, 'A') is the same book as 'A-Chemical-Conception-Of-The-Ether (1).pdf'; pages 32-37 (periodic tables and the x/y ratio pages) carry rotation flags that display them landscape; its digests of those pages are less reliable. Text layer of the two PDFs is word-for-word identical outside OCR layout noise on pp.32-36. Further points found by the QE and reviewers: Mendeleev cites Dewar's 1902 Belfast presidential address as kindred (the highest atmosphere 'the province of hydrogen and of the argon analogues', only a few steps from a lighter gas filling space) [read: PDF p.51]; he says the gas-ether 'does not require the recognition of a peculiar fourth state' (Crookes) [read: PDF p.22]; he rejects unity of matter on the ground that 'a distinction must be made between matter, force, and mind' [read: PDF pp.40-41]; he cites Stoney's and Rogovsky's argument (printed 'Rostovsky') that H and He escape Earth's atmosphere, with his own footnote that both were 'very soon' found there. The limits of x are printed 0.000,000,96 and 0.000,000,000,053, i.e. 9.6e-7 and 5.3e-11 (digest 37bf6d.02 pp.49-50 gives wrong decimals); the adopted 'nearly one millionth' is the upper edge of that range. Kelvin's lower bound is quoted as printed; Kelvin's original was not found.

Key claims

• Mendeleev proposes that the ether is a real chemical element: a monatomic gas, like helium or argon, that cannot combine chemically.
• A new 'zero group' of inert gases (He, Ne, Ar, Kr, Xe) belongs in the periodic table, plus a 'zero series' above it that holds the ether element x.
• Element x (the ether) has an atomic weight of about one millionth of hydrogen's and a molecular speed (rms) of about 2,250 km/s at an assumed space temperature of about -80 degC.
• The limits on x follow from escape velocities: x must be light enough to leave the Earth and the Sun (x < 0.038 and x <= 0.000013, H = 1), yet be held by massive stars (x >= about 0.00000000005 for a 120-million-solar-mass body that would hold light-speed particles).
• A second unknown element y, lighter than hydrogen (atomic weight at most 0.4, density below 0.2), may be coronium, the source of the green solar-corona line near 531.7 nm.
• The ether has weight and is all-permeating (like hydrogen in palladium), and ether atoms accumulate on heavy radioactive elements (U, Th, Ra); radioactivity, the Curie zinc-sulphide fluorescence demonstration and Dewar's low-temperature phosphorescence are offered as supporting phenomena.
• Mendeleev rejects the unity of matter, electrons as subdivisions of the atom, and transmutation (Emmens, Fittica), while accepting the unity of the ether substance.

Relevance: The central primary document of the project: Mendeleev's own statement, in his last years, of the ether-as-element hypothesis and of elements lighter than hydrogen.

Mainstream conflict: Mainstream physics since Michelson-Morley (1887) and special relativity (1905) holds there is no ether medium; no element lighter than hydrogen exists (atomic number 1 is the lowest); the green coronal line (531.7 nm as printed by Mendeleev; 530.3 nm modern value) was later identified as highly ionised iron, Fe XIV, by Grotrian and Edlen, 1939-42 [web: https://en.wikipedia.org/wiki/Coronium, per the arbiter]; Stewart's sentence on this is ambiguous and credits the name 'coronium' to 'Gruenwald'. Mendeleev's use of a single assumed temperature and escape-velocity cut-offs is his own method.

Longmans, Green 1904 English translation of Mendeleev's essay (printed pp.1-51, PDF pp.9-59), from the Cornell University Library copy scanned by the Internet Archive (archive.org/details/cu31924012371096). It has no preface or headings. Mendeleev argues that the ether should be treated as a chemical element, the lightest inert gas, and places it in a new 'zero series' of the periodic system above a new 'zero group' of noble gases (argon group), with a second unknown element y (possibly coronium) between the ether and hydrogen. He recalls his 1874 work with Kirpichev (spelled 'Kirpitchnikoff'/'Kirpichnikov' in the English text) on departures from Boyle's law at low pressure, and argues that the ether must have weight (citing Lord Kelvin's lower bound of about 1e-16 g per cubic metre) and must permeate all bodies as hydrogen permeates palladium. He estimates atomic weights of y (at most 0.4 from the Li:H ratio of 6.97) and x (at most 0.17 from noble-gas ratios, then far smaller from kinetic limits). The kinetic argument uses the root-mean-square (rms) molecular speed v = 1843 sqrt(2(1+at)/x) m/s (the mean speed is 1694 m/s), with space temperature taken as -80 degC, and compares with escape velocities of Earth (about 11.2 km/s), Sun (about 608 km/s) and heavy stars (up to 50 solar masses, about 2,240 km/s). He adopts for x an atomic weight near one millionth of hydrogen and a velocity of about 2,250 km/s. He cites radioactivity (a Curie flask demonstration of zinc sulphide fluorescing when joined to a radioactive solution) and Dewar's low-temperature phosphorescence as support, calls it 'a series of thoughts' and a hypothesis (PDF p.39), and says its object is to bring the question to the fore. PDF pp.61-100 are a Longmans publisher's catalogue ('A Select List of Books', not part of the essay); pp.8, 60 and 101-104 are blank. Duplicate of 'A-Chemical-Conception-Of-The-Ether.pdf': same 1904 translation, same Internet Archive scan, 104 pages, not byte-identical (different MD5), differing only in page-rotation flags on pp.32-37 (here /Rotate 0, so those pages show portrait). Deep-read comparison found no word or number that differs. Counted as an edition/copy of one work. Further points found by the QE and reviewers: Mendeleev cites Dewar's 1902 Belfast presidential address as kindred (the highest atmosphere 'the province of hydrogen and of the argon analogues', only a few steps from a lighter gas filling space) [read: PDF p.51]; he says the gas-ether 'does not require the recognition of a peculiar fourth state' (Crookes) [read: PDF p.22]; he rejects unity of matter on the ground that 'a distinction must be made between matter, force, and mind' [read: PDF pp.40-41]; he cites Stoney's and Rogovsky's argument (printed 'Rostovsky') that H and He escape Earth's atmosphere, with his own footnote that both were 'very soon' found there. The limits of x are printed 0.000,000,96 and 0.000,000,000,053, i.e. 9.6e-7 and 5.3e-11 (digest 37bf6d.02 pp.49-50 gives wrong decimals); the adopted 'nearly one millionth' is the upper edge of that range. Kelvin's lower bound is quoted as printed; Kelvin's original was not found.

Key claims

• Mendeleev proposes that the ether is a real chemical element: a monatomic gas, like helium or argon, that cannot combine chemically.
• A new 'zero group' of inert gases (He, Ne, Ar, Kr, Xe) belongs in the periodic table, plus a 'zero series' above it that holds the ether element x.
• Element x (the ether) has an atomic weight of about one millionth of hydrogen's and a molecular speed (rms) of about 2,250 km/s at an assumed space temperature of about -80 degC.
• The limits on x follow from escape velocities: x must be light enough to leave the Earth and the Sun (x < 0.038 and x <= 0.000013, H = 1), yet be held by massive stars (x >= about 0.00000000005 for a 120-million-solar-mass body that would hold light-speed particles).
• A second unknown element y, lighter than hydrogen (atomic weight at most 0.4, density below 0.2), may be coronium, the source of the green solar-corona line near 531.7 nm.
• The ether has weight and is all-permeating (like hydrogen in palladium), and ether atoms accumulate on heavy radioactive elements (U, Th, Ra); radioactivity, the Curie zinc-sulphide fluorescence demonstration and Dewar's low-temperature phosphorescence are offered as supporting phenomena.
• Mendeleev rejects the unity of matter, electrons as subdivisions of the atom, and transmutation (Emmens, Fittica), while accepting the unity of the ether substance.

Relevance: The central primary document of the project: Mendeleev's own statement, in his last years, of the ether-as-element hypothesis and of elements lighter than hydrogen.

Mainstream conflict: Mainstream physics since Michelson-Morley (1887) and special relativity (1905) holds there is no ether medium; no element lighter than hydrogen exists (atomic number 1 is the lowest); the green coronal line (531.7 nm as printed by Mendeleev; 530.3 nm modern value) was later identified as highly ionised iron, Fe XIV, by Grotrian and Edlen, 1939-42 [web: https://en.wikipedia.org/wiki/Coronium, per the arbiter]; Stewart's sentence on this is ambiguous and credits the name 'coronium' to 'Gruenwald'. Mendeleev's use of a single assumed temperature and escape-velocity cut-offs is his own method.

Article in Foundations of Chemistry 21:3-9 (2019; doi 10.1007/s10698-018-9312-0, published online 2018), by Philip J. Stewart, Department of Plant Sciences, Oxford. It is a modern secondary review of Mendeleev's predictions (J = journal page, PDF page = J minus 2). Mendeleev's detailed 1871 predictions of eka-aluminium, eka-boron and eka-silicon were confirmed as gallium (1875), scandium (1879) and germanium (1886). The abstract says 'Eleven other predictions'; the body names ten element predictions: six in the 1871 quotation (eka-cesium 175, dvi-cesium 220, eka-niobium 146, eka-tantalum 235, eka-manganese 100, tri-manganese 190) and four 'scattered through Mendeleev's works' (eka-molybdenum 140, eka-cadmium 155, eka-iodine 170, dvi-tellurium 212) [read: J pp.4-5]. The eleventh is not identified. Stewart counts five as successes: technetium (100), rhenium (190 vs 186.2), polonium (212 vs 209), francium (220 vs 223) and protactinium (235 vs 231); five (RAM 140-175: eka-molybdenum, eka-niobium, eka-cadmium, eka-iodine, eka-cesium) fell in the lanthanide 'dead zone' and he counts them as one repeated mistake. His success criterion: a prediction succeeds if 'it must fall on a higher analogue of the element on which it is based and have appropriate properties' [read: J p.5]. (The text also gives eka-niobium as 146 in the 1871 quote and 145 in the failure list, and dates germanium 1886 on J p.3 and 1885 on J p.6.) Career context [read: J pp.6-7]: after December 1871, which Gordin calls 'the death of all research by Mendeleev on the periodic system', he turned from 1872 to gas laws under a new Commission for Research in the Elasticity of Gases, with the ambition 'to establish the nature of the luminiferous aether'; he resigned from this work in January 1881. Stewart writes that Mendeleev's 'interest in the nature of the aether led naturally into concern with spiritualism'; in May 1875, at Mendeleev's instigation, the Russian Physical Society set up the Commission for the Investigation of Mediumistic Phenomena 'with the object of re-establishing science as the source of truth on such matters'; Mendeleev battled for the scientific view for a year until it became clear the Commission was influenced by scientists who were themselves spiritualists (source: Gordin 2004 pp.81-111). The link from ether to spiritualism is Stewart's characterization. Stewart on the 1904 table [read: J p.8]: 'Mendeleev's main modification was to add the aether in a new row zero. He also added coronium as a noble gas lighter than hydrogen, and he marked blanks for six more elements between hydrogen and helium.' His own Fig. 2 (the 1904 table, J p.7; page image) shows only x in row 0 and y beside hydrogen in row 1, with no row of six blanks between hydrogen and helium; this sentence is therefore Stewart's statement, not supported by his figure. The same sentence says the green coronal line was 'eventually identified as due to a highly ionised form of iron and named coronium by Gruenwald' [12]; note 12 is Gruenwald, Chemical News 56 (2 Dec 1887) p.232, on water-vapour spectra, and the sentence is ambiguous on who named or proposed what (the Fe XIV identification is Grotrian and Edlen, 1939-42, per the arbiter's web check). Werner [read: J p.8, Fig. 3 page image]: Werner's 1905 table (Berichte der deutschen chemischen Gesellschaft 38:914-921) 'snipped out' the dead zone, produced nearly the modern long form, and 'also included spaces for two elements lighter than hydrogen and two elements between hydrogen and helium, but this just shows that such ideas were around at the time and were not an innovation of Mendeleev's'. Werner won the 1913 Nobel Prize in Chemistry. The figure as printed shows three placeholders on the row above hydrogen and one before He (four in all, split 3+1). Nobel [read: J p.8, no footnote]: Mendeleev 'was nominated for the 1906 prize but, by 5 votes to 4, it was awarded to Henri Moissan'; both died the following February (1907). Tally [read: J pp.8-9]: Scerri's scorecard counts eight successes, five failures and also aether and coronium (8 of 15, 'half'); Stewart's own: eight successes (3 + 5), one multiple error, two irrelevancies (aether, coronium: 'as completely detached as ectoplasm from chemistry'). He notes that 'his 1904 article now figures on esoteric websites' (note 16 cites rexresearch.com). The article closes with a warning from superheavy-element studies (oganesson, copernicium, flerovium) against a new 'dead zone' of rigid group assumptions.

Key claims

• Mendeleev's detailed predictions of gallium, scandium and germanium were confirmed in 1875, 1879 and 1886.
• Of the ten element predictions named in the body (the abstract says eleven), five (Tc, Re, Po, Fr, Pa) were broadly successful.
• Five predictions with atomic weights 140-175 failed because of his table structure and the lanthanide 'dead zone', one mistake repeated.
• Stewart states that Mendeleev's ether (row zero) and coronium had no connection to known element properties and counts them as irrelevancies, not predictions.
• Stewart states that Mendeleev left the periodic system around December 1871 and spent 1872-1881 on gas elasticity aimed at the nature of the ether, and that this led to the 1875 spiritualism commission (Stewart's characterization).
• Stewart states that Werner's 1905 table also left spaces for elements lighter than hydrogen, showing such ideas were around at the time.
• Stewart states that Mendeleev's 1904 table has blanks for six more elements between hydrogen and helium; his own Fig. 2 shows only x and y.

Relevance: Secondary context from a modern chemist: places the 1902 ether essay inside Mendeleev's career (the 1872-1881 ether-motivated gas programme, the 1875 spiritualism commission, the 1906 Nobel vote), scores his predictions, and records Werner's 1905 sub-hydrogen spaces as evidence that the idea was not unique to Mendeleev. Several of its statements about the 1904 table and coronium are contradicted by its own figure or footnote.

Mainstream conflict: None: this is a mainstream historical assessment. It treats the ether and coronium additions as unsupported, which is the author's view. Internal slips: 'six more blanks' not in his Fig. 2; 'gold was missing' while Fig. 2 shows Au = 197.2; the Gruenwald sentence.