Talk:Dmitri Mendeleev/Archive 1

Date of birth
eo:Dmitri MENDELEEV, de:Dimitri Iwanowitsch Mendelejew and Britannica say the date of birth is Feb 8. fr:Dmitri Mendeleïev says Feb 7. Which is correct? Angela. 20:47, Feb 9, 2005 (UTC)
 * State Russian Encyclopedia has Feb 8. It is an authority to be relied upon. See http:// tinyurl.com/6argz The same date is found on numerous Ru-sites. See http:// tinyurl.com/6exqv Ghirlandajo 07:11, 10 Feb 2005 (UTC)


 * Don't forget how easily misinformation can be copied from a wikipedia in one language to those in others! Julian / Gregorian calendar differences have added to the confusion here. I have amended the dates to (Gregorian) 8.II.1834&mdash;2.II.1907 as shown in Russian-language sources. -- Picapica 23:15, 15 July 2005 (UTC)

petroleum quote
BUt IN: he was gay and wanted to make out with boys Removed the following:
 * Mendeleyev also studied petroleum origin and concluded that it has deep origins from earth's interior. "The capital fact to note is that petroleum was born in the depths of the Earth, and it is only there that we must seek its origin."

A direct quote must be sourced. Also, I don't see this as an achievement. Vsmith 02:50, 17 August 2005 (UTC)

I've read a copy of Mendeleyev's paper for Russian Chemistry Society meeting of 15 October 1876. This translation is very close to Mendeleyev's words.

And there is another well-known Mendeleyev's quote about petroleum: "Нефть - не топливо, топить можно и ассигнациями" ("To burn oil means to stoke a stove with banknotes" - translation taken from http://www.opec.ru/library/article.asp?tmpl=def_article_print&d_no=2021&c_no=66&c1_no=).

Order of birth
Nature says 14 is an error, but what is the source for the supposedly correct 13? What are the names of the previous 12? Also were there any still-births in the family and do they get counted? My grandmother had a still-born girl and she was given a name, Anna, I believe, before she was buried. Hackwrench 01:50, 16 December 2005 (UTC)
 * I agree we should check this very carefully.

Errors/omissions corrected

 * 1) 'patented modern vodka recipe' -- actually, afaict, he just wrote about mixing alcohol and water in his doctoral thesis; which related to the standard proof of vodka (something noted correctly later in the article).

Not quite corrected yet:
 * 1) His birth order.  Before it was stated, perhaps incorrectly; now it is elided.  Not certain that "13th" is correct as the Nature.com review suggests; needs sourced verification and perhaps subtletly in explaining source variations.
 * 2) The relationship of his work to Dalton's.
 * 3) Was DM really the only one to predict the properties of unknown elements?
 * 4) Was DM's questioning of accepted atomic weights correct in each instance? only in some?  Was he the only one to so question?
 * 5) Is he really 'given credit for' introducing the metric system to Russia?  These all sound like the stuff of legend, with a kernel of truth but rather far from fact.

It seems likely that many of the 'mistakes' found in both EB and WP are significant omissions [both in this and in other biographies]. We should be able to get closer to 19 than the above list, however. +sj + 04:47, 16 December 2005 (UTC)


 * 1) I'm not sure about the English tradition, but St. Petersburg was then known as Peterburg (Петербург) in Russia.--ACrush ?!/© 14:21, 18 December 2005 (UTC)

Periodic table
It would be nice to have an image of one, don't you think so? Unfortunately, Periodic table seems to have a nice table - but no picture. If you know of one we can use on Wiki, or can make one - it would be a nice addition.--Piotr Konieczny aka Prokonsul Piotrus Talk 04:52, 16 December 2005 (UTC)
 * Electronegativity has a good one.the1physicist 23:06, 16 December 2005 (UTC)
 * It's another table, I am afraid. Pretty, but rather too large for this article.--Piotr Konieczny aka Prokonsul Piotrus Talk 23:15, 19 December 2005 (UTC)

Sourcing
I can understand why this has 19 errors: the sourcing is positively terrible! I know that people took some time on this, however they must have gotten their material from somewhere! I suggest that we cite all the facts in this article using and note. - 211.30.173.113 04:16, 18 December 2005 (UTC)
 * Well said.--Piotr Konieczny aka Prokonsul Piotrus Talk 23:15, 19 December 2005 (UTC)

Mendeleyev the bigamist
"... he married Feozva Nikitichna Leshcheva; the marriage ended in divorce, though not before he had married Anna Ivanovna Popova."  If this is true, I think we need to state explicitly that he was a bigamist. Bigamy is hardly an insignificant or trivial matter in Russian society. JackofOz 21:46, 19 January 2006 (UTC)

Number of siblings
I am adding this here because this note is too big for the article. -- Pinktulip 16:28, 28 January 2006 (UTC)

The number of Mendeleev's siblings is a matter of some historical dispute. When the Princeton historian of science Michael Gordin reviewed this article as part of an analysis of the accuracy of Wikipedia for the December 14, 2005 issue of Nature, he cited as one of Wikipedia's errors that "They say Mendeleev is the 14th child. He is the 13th surviving child of 17 total. 14 is right out." However in a New York Times article from January 2006, it was noted that in Gordin's own 2004 biography of Mendeleev, he also had the Russian chemist listed as the 17th child, and quoted Gordin's response to this as being: "That's curious. I believe that is a typographical error in my book. Mendeleyev was the final child, that is certain, and the number the reliable sources have is 13." Gordin's book specifically says that Mendeleev's mother bore her husband "seventeen children, of whom eight survived to young adulthood," with Mendeleev being the youngest. See: George Johnson, "The Nitpicking of the Masses vs. the Authority of the Experts" New York Times (January 3, 2006) (online); "Supplementary information to accompany Nature news article 'Internet encyclopaedias go head to head' (Nature 438, 900-901; 2005)", posted on the Nature website December 22, 2005 (PDF); Gordin 2004, p. 178.

Nature magazine comparison
This was one of the 42 articles that Nature (journal) compared with the Brittanica version. (Link here) Somebody has already corrected the 13th child bit, but it also states that this article "incorrectly describes how Mendeleev's work relates to that of British chemist John Dalton." I don't know enough on the subject to figure out what they are talking about, but I would guess somebody here does. Cheers, BanyanTree 20:02, 14 December 2005 (UTC)
 * I've requested Nature actually publish the errors in Wikipedia, hopefully, that will help us get it sorted out. In the meantime, we'll have to bear the template. &mdash; Ambush Commander (Talk) 20:55, 14 December 2005 (UTC)

The paragraph about this article says "The most error-strewn article, that on Dmitry Mendeleev, co-creator of the periodic table, illustrates this. Michael Gordin, a science historian at Princeton University who wrote a 2004 book on Mendeleev, identified 19 errors in Wikipedia and 8 in Britannica. These range from minor mistakes, such as describing Mendeleev as the 14th child in his family when he was the 13th, to more significant inaccuracies. Wikipedia, for example, incorrectly describes how Mendeleev's work relates to that of British chemist John Dalton. "Who wrote this stuff?" asked another reviewer. "Do they bother to check with experts?"" WAS 4.250 05:40, 15 December 2005 (UTC)

As best that I can make out about the Dalton comment: Dalton pointed out that compounds (two or more elements) arose from fixed ratios. For example, water was some fixed ratio of hydrogen to oxygen. In contrast, a single-phase solution can cover a wide, continuous range of concentrations, from zero to saturation, thus no fixed ratio of solute to solvent applies. In metalurgy, you can make "solid solutions" or alloys where you can go between all of one metal and all of some other metal. One example: brass, which is copper and zinc. There is no brass "molecule", thus no fixed ratio. -- Pinktulip 02:32, 29 January 2006 (UTC)

Adultry should be pointed out clearly
It is not perfectly obvious from the text that good 'old Dmitri committed adultery. It is a service to the reader to make this clear. -- Pinktulip 23:10, 6 February 2006 (UTC)
 * It already says clearly that he married the one before divorcing the other; sexual misconduct is not the kind of detail encyclopedic articles about scientists go out of the way to draw attention to, unless it is relevant to his career. If I remember correctly, I think this actually did cause some political trouble for him, but unless the context is included, I find it unnacceptable (but I'm not sure of that, so don't use that without a source).  The phrasing of the line about adultery seems to make an implicit judgment that in fact he should have been prosecuted, without any context on the laws and culture he was living in.  How about instead, something to the effect that what he did was illegal?  As it is now, it is definitely out of place, so I'm removing it again.--ragesoss 23:30, 6 February 2006 (UTC)


 * And wasn't the issue about bigamy, rather than adultery? --Fastfission 23:43, 6 February 2006 (UTC)


 * If you want to add that info back in, here is some background to make it not so awkward (paraphrased from Michael Gordin's book, pp 137-138):

(note that all dates are in the old Russian style, using the Julian calendar) Because his first marriage had "started to sour", when he moved Petersburg to be at the center of the Russian scientific world at St. Petersburg University, he left his family at their estate near Moscow. He began courting Popova in August of 1876, becaming despondent and even contemplating suicide when she left for Italy in December of 1880. He followed her to Rome in 1881 and threatened to commit suicide if she didn't agree to marry him. His wife then sued for divorce on the grounds of adultery; their marriage ended officially on February 23, 1882. (His first child with Popova was born December 1881, but "postdated to the spring of 1882). However, his second marriage was technically illegal because the Russian Orthodox Church required a period of seven years before remarriage after divorce, making him "a publicly acknowledged bigamist".  His failure to be elected to the Russian Academy of Sciences (he was being considered in the late 1870's into the early 1880s) was partly (among many other reasons) a result of his divorce and the surrounding controversy.

As Gordin describes it, it was more an issue of religion and public morality than law, per se.

I hope that helps.--ragesoss 23:59, 6 February 2006 (UTC)


 * I've fixed that part. I'll try to rework the whole biography section some time soon; looking over Gordin's book made me remember how interesting his life was (and basically none of the cool stuff is in the article).--ragesoss 03:32, 7 February 2006 (UTC)

Errors ID'd by Nature, to correct
The results of what exactly Nature suggested should be corrected is out... italicize each bullet point once you make the correction. -- user:zanimum

Reviewer: Michael Gordin, Assistant Professor of History of Science, Princeton University, New Jersey, USA.


 * They say Mendeleev is the 14th child. He is the 13th surviving child of 17 total. 14 is right out. 
 * Between 1859 and 1861 Mendeleev spent no time in Paris beyond a brief visit. He was in residence the entire time in Heidelberg.
 * He also did not work on gases at all, but instead the capillarity of liquids in this period.
 * He did not study the spectroscope with Kirchhoff.
 * I notice that the correction simply removes mention of Kirchhoff. Are we sure he studied the spectroscope at all? —Steven G. Johnson 21:35, 22 December 2005 (UTC)


 * He got the job at the Technological Institute in 1864, not 1863.
 * His first wedding is in 1862, not 1863.
 * Mendeleev was not actually dismissed from the University because of political activities. This contention has been invalidated by recent research.
 * M did not work out the 40% by volume standard for Russian vodka (it was established earlier by the British for gin), and he certainly never patented it.
 * Removed, but not replaced with a clarification or correction. The statement was "Mendeleev is often credited for the scientific justification of the "optimal" ratio of alcohol of 40% (80 proof) used in vodka. The source for the attribution was his doctorate thesis "On Composing Alcohol with Water". The thesis dealt primarily with the physical properties of water-alcohol solutions, such as density." That would need verification for what his paper actually said and support for "often credited. - Taxman Talk 23:36, 27 December 2005 (UTC)


 * Newlands published his work first in 1864, not 1866.
 * This has been "corrected" in this article (but not Newlands') without citation. According to this site Newland's first paper was published in 1863 in Chemical News. His paper actually titled "On the Law of Octaves" was published in 1865, though what is now known as that may have been in an earlier paper, and may be part of the confusion. - Taxman Talk 23:36, 27 December 2005 (UTC)


 * Mendeleev's work was also produced in the course of writing a textbook, and not originally a classification of the elements, as Newlands was. The classification emerged by accident, not as the result of a deliberate search for a system.
 * Also, Meyer's table was indeed a categorization by both weight and valence in 1864, not just by valence alone. (All 2-dimensional tables include weight as one axis in the 1860s.)
 * This was my mistake (?). I rephrased the following excerpt from Julius Lothar Meyer article: In 1864, Meyer published an early version of the periodic table, containing 28 elements classified into 6 families by their valence—the first time that elements had been grouped and ordered according to their valence. Work on organising the elements by atomic weight had hitherto been stymied by inaccurate measurements of the atomic weights. into and classified not by atomic weight, but only by valence. Cmapm 23:49, 10 April 2006 (UTC)
 * In the paragraph on the chemical ether, they make it sound like the lighter of the two proposed new elements was meant to be chemically inert. Actually, the other proposed, slightly heavier element (coronium), was *also* supposed to be chemically inert.
 * The paragraph on solutions research gets M's position exactly backwards: he is trying to show that Dalton's laws *don't* apply, not that they do.
 * M's version of gunpowder is "pyrocollodion," not "pyrocollodium."
 * It was not in fact adopted by the Russian navy, which commissioned it.
 * Omission: No mention at all of his importance as a public intellectual in late Imperial Russia. There is also no discussion of his role as an economic thinker, his work on the theory and practice of protectionist trade, his work on agriculture, etc.
 * In the first paragraph, the entry states that there were two competing versions of the periodic table. There were at least five competing variants by different people during the 1860s. Throughout the entry, there is a collapse to just M's and Lothar Meyer's. These are the last two and the most complete, but it is an unfair reduction of the historical picture, and it tends to overdramatize the story (as this entry often does).
 * This first paragraph also makes it sound like the correction of the atomic weights was more radical than the prediction of new properties of elements. It was the latter which was far more controversial. Essentially all periodic systems proposed revisions of existing accepted atomic weights, which were much less fixed than the entry suggests.
 * M's weddings are presented a bit misleadingly. He was indeed married to two women, but for a period of time (a few months) was married to both of them, leading to accusations of bigamy -- although no prosecution.

In general, please don't simply blindly make the correction. For one thing, reviewers can sometimes make mistakes. For another thing, you could end up correcting the symptom but not the disease&mdash;if a particular statement was added without checking, then it could be that the problems in the surrounding text go deeper than what the reviewer pointed out. —Steven G. Johnson 21:37, 22 December 2005 (UTC)

Please note corrected error at /Wikipedia:External_peer_review/Nature_December_2005/Errors.--Piotr Konieczny aka Prokonsul Piotrus Talk 01:38, 24 December 2005 (UTC)

Anybody knows, whether some sources were cited in that "Nature" article or not? Cmapm 23:49, 10 April 2006 (UTC)

French?
Is it likely that Mendeleyev would have written in French? Carcharoth 10:27, 27 July 2006 (UTC)

Spelling of first name
Dmitri? Dimitri? Dimitry? The text uses all 3. Can we use just one, for consistency? riana_dzasta 03:42, 22 November 2006 (UTC).

Interesting picture
This is an interesting sculpture of Mendeleev and the periodic table. I found the picture on Flickr, but it doesn't say more about the location. From the context, I suspect it is in Bratislava, but I'm not sure. Does anyone here know? In any case, the picture could be useful for this article. It has a free license.
 * [[Image:Periodic table monument.jpg|400px]]

-- Itub 01:26, 5 January 2007 (UTC)


 * Apparently it is in front of the Faculty of Chemical and Food Technology of the Slovak University of Technology in Bratislava, Slovakia. Itub 17:01, 10 January 2007 (UTC)

Small Mistake
After the sentence following the table, you've added an extra period. And also, why is this page locked from editing? --86.12.232.113 21:14, 21 March 2007 (UTC)

Removed ref
J. D. Redding 23:06, 11 April 2007 (UTC)
 * User:JzG removed the following
 * An Attempt Towards A Chemical Conception Of The Ether

Spelling of SECOND name
His last name is Mendeleev.

As Mendeleev published his ''ОПЫТЪ СИСТЕМЫ ЭЛЕМЕНТОВЪ. осңованной на ихъ атомкомъ вѣсѣ и химическомъ ходствѣ, the Speculative System of Elements, based on their atomic weights and chemical similarities'', in 1869, the spelling reform of 1918 doesn't influence him. The publication is signed with Д. Менделѣевъ. Therefore, it would be IMHO appropriate to write the surname in the original spelling.80.146.109.154 15:34, 22 July 2007 (UTC)

Another small mistake -- water to ethanol
I tried to correct this but the faithful wikipedia folk decided to put it back to the incorrect form... To wit:  I said 40% ethanol is 1 part ethanol and 4 parts water (turns out it is 1 part ethanol, 5 parts water) -- not 2 like the page wants to extol....

Consider: 100mL of vodka. If 60% (60mL) is water, water density is 1g per mL, so it is 60g of water. H2O = 1+1+16 = 18g/mole so we have 3.33 moles of water. 40% ethanol is 40 mL of ethanol. At a density of 0.77g/mL we have 30.8g of ethanol. Ethanol is CH3-CH2-OH or 12+3 + 12+2 + 16+1 or 46g/mole -- so we have ~.67 moles of ethanol. Total moles = 4. 0.67 is 1 part of 6, or, 1 part ethanol 5 parts water -- I will change it again now. —Preceding unsigned comment added by 76.172.56.48 (talk) 07:18, 19 December 2007 (UTC)

Radioactive Liquids?

 * Some people laughed at Mendeleev for predicting that there would be more radioactive liquids, but he was right when Ga (Gallium) and Ge (Germanium) were found in the future fitting perfectly into the two missing spaces. [3]

I have little formal training in chemistry, so this could easily be my own misunderstanding, but according to this periodic table, neither Ga nor Ge are radioactive liquids.

Slvrstn (talk) 01:09, 31 December 2007 (UTC)

I corresponded with the author of the cited book. He confirmed that the reference to radioactive liquids was incorrect. I removed it and rewrote that paragraph.

Slvrstn (talk) 08:53, 15 January 2008 (UTC)

Crap
This article is pretty much complete crap. It only mentioned his creation of the periodic table in the intro. I would suggest cutting this article back to a stub, and weeding out most of the tangental and poorly sourced material. -Ravedave (talk) 17:30, 25 September 2008 (UTC)


 * I agree that the Periodic Table needs more material in the body. That is, after all, the one thing most people know him for.  However, it's not the only thing he did in his entire life, and the rest of what's there is perfectly OK.  It helps to give a more rounded picture of him.  This is an article on Mendeleev and his life and works, not just the PT.  I'd hardly call it "crap".  --  JackofOz (talk) 20:59, 25 September 2008 (UTC)


 * I agree that the material should be kept because it provides a better all around picture of Mendeleev's life. But I also agree that the existing material lacks inline citations. This should be somehow addressed. Dr.K. (talk) 22:42, 25 September 2008 (UTC)
 * I restored the material on the Periodic table which was removed on May 7, 2008.--Tubesidiom (talk) 04:49, 28 September 2008 (UTC)


 * Good work. It went unnoticed for such a long time. 17:24, 29 September 2008 (UTC)

Vodka
Mendeleev has NOT invented vodka. Please remove this bullshit! —Preceding unsigned comment added by Pavelgubarev (talk • contribs) 10:28, 3 September 2008 (UTC)
 * It is not tha he invented Vodka but that he was simply involved in defining a regulatory standard minimum for its alcoholic content.--Tubesidiom (talk) 04:49, 28 September 2008 (UTC)

Anyway, the statement "vodka should be produced in the ratio of one molecule of ethyl alcohol diluted with two molecules of water, giving a dilution by volume of approximately 38% alcohol to 62% water" is wrong. If you (that's a "generic you") do the calculations, you'll see that to have two molecules of water per molecule of ethanol you need to have 62% ethanol and 38% water--exactly the opposite of what the article says. And this is pretty far from the composition of most current vodkas, so there's something fishy about the story. --Itub (talk) 16:53, 29 September 2008 (UTC)

I removed this paragraph: The classic Russian and Polish vodka is 40% ABV (USA 80 proof). This can be attributed to the Russian standards for vodka production introduced in 1894 by Alexander III from research undertaken by the Russian chemist Dmitri Mendeleev. According to the Vodka Museum in Moscow, Mendeleev found the perfect percentage to be 38. However, since spirits in his time were taxed on their strength, the percentage was rounded up to 40 to simplify the tax computation. Because it looks like it was plagiarized. If a real source can be found, and the language cleaned up, it would be useful to include. John Duncan (talk) 00:53, 25 March 2009 (UTC)

Life - Sourcing

 * His grandfather Pavel Mendeleev, a Jewish merchant from Shklov, converted to Orthodox Christianity in 1804 and moved to St.Petersburg.

What is the source of this information?

I have noted this quote on a couple of unofficial sites on the Internet, which could account for both Mendel and Sokolov being Jewish names in general, the latter often associated with this area. Can anyone verify this from an authoritative biographical source?


 * Source is Morris. His bibliography includes a Russian biography of Mendeliev. The priesthood is doubted, but I would definitely be happy to hear from someone living nearby to check out the church records.
 * Please see my answer below (cryptojew) including sources and questions -- Pashute (talk) 10:47, 24 June 2009 (UTC)

About Mendeleevs ancestors
Mendeleev had no Jewish ancestors. His grandfather was a Russian priest Pavel Sokolov - this is one of the most common Russian surnames. While studying at the seminary, his sons have received different names - this is an old tradition of the clergy. Dmitri's father - Ivan received a sobriquet Mendeleev (on behalf of landowner Mendeleev, next to the possession of which they lived), about his brothers - see in the RU-wiki (where indicated authoritative sources). I am archivist, and I researched the life of Mendeleev 38 years. Merchants and industrialists Kornilevy - the ancestors of the mother a scientist. On this line there is a hypothesis of Kyrgyz origin.

Error reason: Origin name of landlord also has the interpretation of Mendeleev as homonym surname Mendel: in Russian surname first part - word "men" "obmen" "menjat(ь)" - exchange (in en.), and second part - word "dele" - suffix form of word - "delo" - do (in en.). (presumably: the ancestors of Mendeleev landowner involved the replacement of horses on the long period road).

It is Mendeleev's arms - not chemist D. Mendeleev.

Best regards Serge Lachinov (talk) 19:01, 31 July 2009 (UTC)


 * Here is a quote from named in article source:

"Mendeleev's grandfather Pavel Maximovich Sokolov was the priest of the Russian Orthodox Church in a small village of Tikhomandritcy (2 km away from the Udomlya lake, Tver' region, Russia). According to the church books, four of his children, Timofey, Natalya, Tatyana and Praskovya, were given the family name 'Sokolov,' whereas Alexander was recorded as Tikhomandritckii, Vasiliy - as Pokrovskiy, and Ivan - as Mendeleev."

None of known source of information not shown origin Orthodox priest Paul M. Sokolov from Shklov and about his "converting to Orthodoxy from Jewish merchant". --Serge Lachinov (talk) 11:36, 5 August 2009 (UTC)


 * I have searched for the words Jewish and Jew in the preview of the book source allegedely showing Mendeleev's Jewishness and I have found no references to Mendeleev. Since no other reliable sources confirms his Jewishness I have only mentiones Sokolov and Tver region. At any rate the book is just a children popular book on chemists not an in-depth study on mendeleev's biography and unusual claims require serious sourcesAlex Bakharev (talk) 06:51, 10 August 2009 (UTC)

Crypto-jew?
Name Mendel-eev sounds very jewish. Like Felix Mendelson or Menachem Mendel Schneerson. Does Mendeleev has jewish roots?


 * Like Gregor Mendel? The German Catholic monk? Perhaps you can take your retarded anonymous antisemitism elsewhere. John Duncan (talk) 00:55, 25 March 2009 (UTC)


 * Don't confuse racism with ignorance. --Nytemaer (talk) 22:40, 2 April 2009 (UTC)


 * Yes, he is of Jewish ancestry, but he was Christian. He was also a member of an anti-Semitic Russian nationalist and Christian fundamentalist organization 'Union of Russian people' the organization though had many baptisized Jews in their leadership.--79.111.189.134 (talk) 11:21, 11 June 2009 (UTC)


 * His grandfather Pavel Mendeleev converted to Orthodox Christianity in 1804. ( and many other sources originating in The Last Sorcerers).
 * On the other hand, a site dedicated to Mendeleev brings various facts that seem to contradict this information, or at least claim (if both site's facts are correct) that Mendeleev's father was not born a christian, and was converted as well at this date, or before -- Pashute (talk) 10:41, 24 June 2009 (UTC)


 * I'm sure Mendeleev was a MOSSAD agent. —Preceding unsigned comment added by 92.243.167.80 (talk) 17:23, 11 January 2010 (UTC)


 * He wasn't jew at all. Read his biografy in Russian wikipedia... His grandfather's name was Pavel Maximovich Sokolov.

Allegations of racism and "antisemitism" are unfounded, and quite unhelpful. The Cryptojew is a well-established part of Jewish history, ie) Murano Jews in Spain & the Dönmeh in Turkey. This phenomenon also occurred in Russia.  What's important for this article is whether Mendeleev's father was, in fact, an ethnic Jew.  Pashute pointed out that, according to the first citation, Mendeleev's father's ethnicity is not 100% known, it may be in doubt.  Thus, the sentence describing Mendeleev's father's ethnicity ought to be removed or, at least, modified to express uncertainty.--Bureaucracy (talk) 01:11, 10 August 2009 (UTC)

John Newlands
The sentence starting "John Newlands" is ungrammatical, with no main verb. —Preceding unsigned comment added by 86.177.171.194 (talk) 15:08, 15 March 2010 (UTC) The Newlands and Mendeleev articles contradict each other over the prediction of the discovery of Germanium. —Preceding unsigned comment added by 81.154.2.141 (talk) 09:35, 16 March 2010 (UTC)


 * I have fixed the grammar in that sentence and some others in the same paragraph. As for the prediction of germanium, the article on John Newlands links to his original papers with some added modern footnotes. At a quick glance it seems that Newlands "sort of" predicted germanium before Mendeleev - that is, he did suggest an element of approximate mass 73 which would resemble silicon and tin. However his ideas were much less systematic than those of Mendeleev - he made various "predictions" which contradicted each other, and did not predict the properties of germanium in detail as Mendeleev did. So I think that the truth is somewhere between what the two articles say (as is often the case), and that more careful reading is required before changing either article. Dirac66 (talk) 02:47, 27 May 2010 (UTC)

Date of periodic table shown in article
Edit semi-protectedThe caption says Mendeleev's 1869 periodic table. Please change 1869 to 1871. The version displayed is the 1871 version (as correctly stated in the image file). The 1869 version showed related elements in the same horizontal row, not in the same vertical column (as has been done since 1871). The 1869 layout is shown in http://web.lemoyne.edu/~giunta/mendeleev.html, but that page does not have an image of the 1869 publication. —Preceding unsigned comment added by 192.231.124.76 (talk)
 * Yes check.svg Done Thanks. -Atmoz (talk) 21:15, 11 November 2010 (UTC)

Family information?
"At the age of 13, after the death of his father and the destruction of his mother's factory by fire, Mendeleev attended the Gymnasium in Tobolsk. In 1849, the now poor Mendeleev family relocated..." He had 7 sisters and 8 brothers. unclear; if his parents died then who's in his family? adopted by someone??? Dmitri's 68.38.146.5 (talk) 16:53, 1 April 2011 (UTC)

Who else?
...one of the two scientists who created the first version of the periodic table of elements...

So who was the other? I think we should be told! -- Picapica 23:15, 15 July 2005 (UTC)

Julius Lothar Meyer (1830-1895), I think did the same thing as Mendeleev. —Preceding unsigned comment added by 67.158.70.164 (talk) 20:50, 7 September 2008 (UTC)
 * Not the same. Read more about history of chemistry... )) --= APh =-- (talk) 17:49, 11 April 2011 (UTC)

Edit request from 129.79.138.163, 4 July 2011
The following sentence needs to be corrected: "Mendeleev became Professor of Chemistry at the Saint Petersburg Technological Institute and Saint Petersburg State University in 1863" According to on-line versions of "Great Soviet Encyclopedia", and "Encyclopedia Britannica", Mendeleev did not become a Professor at either of these institutions at 1863. Moreover, at Saint Petersburg State University, he was at first a professor of chemical technology. Only later, in 1867, he became the professor of General Chemistry. I would rewrite that as: "In 1864, Mendeleev became a professor at the Saint Petersburg Technological Institute. In 1865, he was also appointed as a professor at the University of Saint Petersburg (now Saint Petersburg State University)." In addition to the two encyclopedias, I also checked that information in: 1. the on-line supplementary material to the article in "Nature" (Nature 438, 900-901; 2005). 2. the biography of Mendeleev by L. A. Chugaev, available in parts on-line at: http://elementy.ru/lib/430731

129.79.138.163 (talk) 21:00, 4 July 2011 (UTC)
 * Yes check.svg Done Jnorton7558 (talk) 22:36, 4 July 2011 (UTC)

Other claimants
I noticed that the Antoine Lavoisier article claims a "periodic table" of 33 elements. Should we mention that?--64.9.237.117 18:50, 18 February 2007 (UTC)
 * Probably not. Thank you for mentioning it though, about Lavoisier, and thoughtfully providing the Wikipedia link! I checked into it, read the page, and dug a little deeper. There were numerous predecessors, of sorts, to Mendeleev's periodic table. The Periodic table entry covers them in detail. That is a more appropriate place, I believe, than here, in the Mendeleev biographical section. I don't think it is an overstatement to say that Mendeleev's concept of the periodic table was on a different order of significance, scale, scope than any of his predecessors. --FeralOink (talk) 17:25, 23 February 2012 (UTC)

Garbled name
A piece commented out, until the garbled name will be fixed. Mikkalai 19:59, 1 Mar 2004 (UTC)
 * In the same year, he married Feozva Nikitchna Lascheva. 


 * It is not garbled however does have a couple typos. The actual name is Feozva Nikitichna Leshcheva. See Russian Wikipedia http://ru.wikipedia.org/wiki/%D0%9C%D0%B5%D0%BD%D0%B4%D0%B5%D0%BB%D0%B5%D0%B5%D0%B2. Feozva or Theozva is the Russian version of the Greek name Theosebia, see http://en.wikipedia.org/wiki/. Patronimic is Nikitichna because her father's first name was Nikita. Last name Leshcheva derived from a Russian name of a fish (leshch).
 * I know for English-speaking people most Cyrillic names are "garbled" but this is not a reason to delete correct information from Wikipedia, without googling it out first. --Rozmysl (talk) 19:26, 2 May 2012 (UTC)

Vodka
As a user already pointed out (see below) the russian wikipedia site holds more information. Among others it claims, that all of the "myths" (Mendeleevs definition of "the" formula, his "law" of setting 38% and/or 40% as ideal ratio) are wrong. Nevertheless his dissertation (doctoral thesis) did cover the topic of mixing spirits (in general, not explicitly vodka!) with water though at HIGH degrees -around 70%!! Again - it's just what i read on the russian site. But the "reference" (russianfood.com) on this site does NOT seem reliable to me. Hence I suggest to just write that Mendeleev's dissertation covered the mixture of water and spirits which apparently got mixed with/expandend by urban legends. --Che-burashka 08:44, 18 March 2011 (UTC)

'Russian Standard'
Many Russians I have talked to have said that the Russian vodka "Russian Standard" is actually the formula for 'the best' vodka, as developed by Mendeleev.

Has anyone else heard this claim? And how likely is it to just be the company’s propaganda and/or simply obliquely related to his work? --Jowe 01:11, 6 March 2006 (UTC)

Reply on Vodka -- if someone can make this more suitable for the article (minus the sarcasm), please go ahead. It is all true: -- We all know that he discovered the periodic table of elements, on which all modern science is based. But few people know how his scientific career began and the "inspiration" (as in "spirit") that preceded the invention of the periodic table. He single-handedly invented...vodka! For his doctoral dissertation in 1865, young Mendeleev decided to study in detail the process of mixing water and alcohol. (Hmmm?!) I guess he spent a great deal in "research" and found out that there was a "compression of mixture", i.e. that the volume of the solution was smaller than the sum of two original volumes (Ha!) I guess the combined volume was smaller, even before all the tasting and sipping :-) The largest compression of the mixture was reached when 45.88% (mass units) of anhydrous alcohol and 54.12% of water were mixed. This is what is now called 40° vodka (80 proof). As a result, 1 liter of 40% vodka weighs 951 grams and vodka in Russia is often measured and sold not by volume (ml), but by weight (grams). To be precise, Mendeleev thought the perfect percentage to be 38%, but since spirits were taxed on their strength, the percentage was rounded up to 40% to simplify computations. As 40% vodka was considered optimal by the professor, the emperor of Russia made him a head of a special commission, a patent was filed and this was introduced as the national standard for vodka which was put in place around 1894-1896. Look it up, if you don't believe me! Bibliographical reference: О соединении спирта с водою "O soedinenii spirta s vodoi" ["On Mixtures of Alcohol with Water"], St. Petersburg, 1865, reprinted in D. Mendeleev, Sochineniia [Collected Works], Izd. Akademii Nauk SSSR, Leningrad, 1949, Vol. 4, 1-52.

The above contradicts the article on russian wikipedia. Namely, Mendeleev studied the alcohol-water solutions irrespective to their use as drinks. By the way, the accurate physical description of such processes remain to be very problematic till now. The proportion 40% was chosen from the point of view of convenience: it is close to 2:3 ratio (probably, by volume - which is simpler to prepare).

The top bar says all the 19 errors have been fixed but under the "Errors ID'd by Nature, to correct" only the first error is Italized. So are they really fixed or did they just forget to Italize the list of errors in the discussion page? ..-Random viewer. You have got to be kidding me. Everyone knows that Mendeleyev published research on vodka. However Russian Standard or Russkiy Standard in Russian is just one of the hundreds of post-1991 vodkas produced in post-USSR countries, with multicoloured labels and stupid names like "Vodka Putin" or "Prince Igor" etc which have nothing to do with original pre-1917 Russian vodkas. Believe me, since I have tasted Soviet and Russian vodkas since 1986. The most memorable was called Vodka Black Death (Chernaya smert) and was sold in 1993-1995 in metal cans (like beer) in Moscow in every corner's kiosk and tasted very close to acetone. The good part I did not turn blind after drinking such stuff. Rozmysl (talk) 06:32, 14 May 2012 (UTC) As for selling vodka in grams in Russia, this is not true. In Russia vodka is sold in milliliters. On the bottle labels you can find either eg. 500 mL or 0,5 L but never grams. Selling liquids in grams is very problematic anyways, how do you imagine it? Using scales in bars? Russia and former USSR is very thorougly standardized country, and all units, sizes, weights etc. are very strictly standardized, so in Russia nothing can be sold "sometimes in grams, sometimes in ml", it is either ml or grams. The truth is, in conversational language people rather say "100 grams of vodka" but not "100 milliliters of vodka", however it still measured in ml. This may be the origin of this misunderstanding. Rozmysl (talk) 06:32, 14 May 2012 (UTC)

Mendeleev or Mendeleyev?
The title and the text spell his name in two different ways. One needs to be decided on and applied consistently. — Ливай | Ⓣ 17:46, 1 October 2005 (UTC)


 * Fixed. 01:28, 15 December 2005 (UTC)
 * But why did you fix it this way? Everywhere else in Wikipedia that I've seen it (and in most other english-language publications) it is spelled Mendeleev... why are we going with the minority?  +sj + 09:28, 15 December 2005 (UTC)

'Mendeleev' is a direct transliteration of a Russian name 'Менделеев' (you can install Russian fonts and check their similarity), but the correct transcription is 'Mendeleyev'. I'm a native Russian speaker, BTW.
 * That could be true, but "Mendeleev" seems to be the prevailing spelling. A search on Google yeilds (as of writing of this comment) 361,000 hits for "Mendeleev" and 92,500 hits for "Mendeleyev".  Thus, I'd stick with "Mendeleev" Ikh (talk) 11:55, 26 January 2006 (UTC)


 * I depends on what transliteration system you use. Let's go with the most common one used in English; whether or not it is indicated that the last "e" is soft or not doesn't seem as important to me as people finding the right name. --Fastfission 15:36, 26 January 2006 (UTC)

Revisited
"Mendeleyev" produces 326,000 ghits, "Mendeleev" 354,000. So it's far from clear cut. WP:RUS advises us to render Russian e as e, except "after vowels", where it becomes ye. That's why, for example, nobody's ever heard of Rudolf Nureev, but everybody knows about Rudolf Nureyev. Same for Sergei Taneyev, Fadeyev, and so on. May we please have Dmitri Mendeleyev as the primary title, with Dmitri Mendeleev as the redirect, rather than the other way around? --  Jack of Oz    ... speak! ...   09:08, 22 May 2010 (UTC) Correct would be Mendeleyev since it corresponds to Cyrillic Менделеев. Mendeleev would correspond to Cyrillic Менделеэв. Cyrillic has two letters E: one is E, same as Latin E, the other is Э. In the beginning of the word or after a vowel E is pronounced like "YEH" and Э is pronounced like "EH". Spelling Mendeleev would mean pronouncing it "Men-deh-leh-ehv" however the true pronounciation is Men-deh-leh-yev. Geographs are very good at this, if you want to understand rules for converting Cyrillic names to Latin, look at a map of Russia. However I do not expect anybody to agree with me, since even most Russians will have no clue how to transliterate their names to Latin properly. Take for example name of the country on Russian postal stamps: they spelled it Rossija (in Latin) for more than 10 years until recently, as apposed to proper Rossiya, since most Russians know Latin (not English) names for Latin letters like "a, be, tse, de, ye, ef, zhe, ash, i, yot" etc, this pronunciation is used in Russian schools to teach kids math. So J for Russians traditionally is "yot" and represents sound "Y" similar to C representing sound TS (same sound as in German word Zeit etc). Rozmysl (talk) 06:44, 14 May 2012 (UTC) In Russia there is city Mendeleyevsk, you can find it via Google maps, this is the correct spelling. Using Google hits to justify spelling is ridiculous. Rozmysl (talk) 06:50, 14 May 2012 (UTC)

Dating/calendar issues
As Russia used the julian calendar back then, the dates are not very explicit... are they julian or gregorian dates? looking at other wikipedias I see various different dates for his birth and death... someone with good russian calendar knowledge could check that? Thanks Srtxg 00:57, 4 Feb 2004 (UTC)
 * The date links to February 7 which mentions only the Gregorian Calendar, so I think it can be assumed to be the new style date. Angela. 20:47, Feb 9, 2005 (UTC)
 * The date of birth is Feb. 8th by Georgian calendar (aka "new style") or Jan. 27th by Julian calendar (aka "old style"). Date of death is Feb. 2nd Georgian and Jan. 20th Julian. Rozmysl (talk) 15:12, 10 December 2012 (UTC)

Periodic table conceived in a dream
I just noticed that the article has no mention of how Dmitri Mendeleev said that he found the structure for his periodic table, in a dream. — Preceding unsigned comment added by 84.13.50.49 (talk) 19:10, 29 May 2012 (UTC)


 * Yes, is a well-known story. — Preceding unsigned comment added by 79.173.85.181 (talk) 03:06, 12 January 2013 (UTC)

Lead paragraph
While all the information stated in the lead is true it seems to be both short and somewhat unprofessional. It has a weird ending sentence ending with an exclamation mark. Can someone better with words and wiki editing than I please have a look at it. Awnman (talk) 22:44, 29 April 2013 (UTC)

Edit request, 5 November 2013
Surcoe (talk) 18:34, 5 November 2013 (UTC) Emmy award. That is all.


 * Red information icon with gradient background.svg Not done: please provide reliable sources that support the change you want to be made. --Stfg (talk) 19:05, 5 November 2013 (UTC)

Semi-protected edit request on 24 July 2014
Please correct broken link, first in the list of external links. Current line says Original Periodic Table, annotated. webserver.lemoyne.edu The correct url is http://web.lemoyne.edu/~giunta/EA/MENDELEEVann.HTML If you keep the text more or less as it is displayed, then the domain name at the end should be changed to web.lemoyne.edu

184.153.238.245 (talk) 20:15, 24 July 2014 (UTC)
 * Yes check.svg Done. Thanks for finding the updated URL! —Mr. Granger (talk · contribs) 23:02, 24 July 2014 (UTC)

Semi-protected edit request on 23 November 2014
There is an absence of a record of Mendeleyev getting a Copley Medal from The Royal Society under his personal information.

http://en.wikipedia.org/wiki/Copley_Medal contains all necessary information and proof links.

Errare humanum est 08:16, 23 November 2014 (UTC)
 * Pictogram voting wait.svg Already done "Though Mendeleev was widely honored by scientific organizations all over Europe, including (in 1882) the Davy Medal from the Royal Society of London (which later also awarded him the Copley Medal in 1905)" Cannolis (talk) 10:50, 23 November 2014 (UTC)

which are either of nearly the same value
The text states, "... which are either of nearly the same value." This is obviously a typo, but I cannot guess what it should be. Does anyone have access to the source to correct this statement, or rephrase it so it makes sense to mortals? Grammar&#39;sLittleHelper (talk) 22:10, 2 January 2016 (UTC)
 * I tried to make the text more readable, is it better now? Alex Bakharev (talk) 00:38, 3 January 2016 (UTC)

Semi-protected edit request on 10 December 2015
Change the death date from 2 February to 20 January

Wikikkkkikipedia (talk) 16:48, 10 December 2015 (UTC)
 * Red information icon with gradient background.svg Not done: Do you have a reliable source indicating that his death was on 20 January? /wia   /tlk  01:14, 11 December 2015 (UTC)
 * Basically the reason for confusion is that Russia at that time used Julian Calendar, and 2 February of Gregorian Calendar is 20 January Julian Calendar. Thus, many sources give 20 January without specifying the calendar. We give Julian dates of birth and death in the lead, I think it is enough. Alex Bakharev (talk) 00:47, 3 January 2016 (UTC)

Atomic Number ?
The Periodic Table is actually laid out by an element's Atomic Number. Previous attempts had always laid it out by atomic weight- Did Mendeleev ever realise this? Surely even if he didn't, we should explain that his way of laying it out and the spaces left corresponded to the Number ie the number of protons in the atom of an element.

IceDragon64 (talk) 14:58, 8 February 2016 (UTC)

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Early life
In this sentence -- "He worked as a school principle and a teacher of fine arts, ..." -- "principle" should be "principal"  — Preceding unsigned comment added by 144.35.5.32 (talk) 19:36, 8 January 2018 (UTC)

Co-creator
Hello. Mendeleev was not "the co-creator" of the periodic table. The Royal Society gives him the credit that is his due. I plan to remove the co-creation sentence in about a month after leaving time for objections here. I'm glad to find that The New York Times found this article to have an amusing number of errors except highlighting a minority opinion isn't funny, it is WP:UNDUE. -SusanLesch (talk) 23:52, 23 May 2017 (UTC)
 * A year later it is still here. I am removing it as per the Fringe theories article, and the dictim "Be Bold". I can find no reliable source for this claim. If some editor feels that it is a valid claim, then they need to include a reliable reference, and in addition show that this idea is not a fringe theory. Nick Beeson (talk) 16:33, 9 February 2018 (UTC)

Semi-protected edit request on 22 May 2018
188.221.67.114 (talk) 20:28, 22 May 2018 (UTC)
 * Red question icon with gradient background.svg Not done: it's not clear what changes you want to be made. Please mention the specific changes in a "change X to Y" format and provide a reliable source if appropriate. - LouisAragon (talk) 20:37, 22 May 2018 (UTC)

Anyone know what "J" is supposed to be?
Help plz --2602:306:CE62:8430:B8E9:76E9:4C00:2749 (talk) 19:22, 8 June 2018 (UTC)
 * Assuming you mean the "J=127" entry in File:Mendelejevs periodiska system 1871.png, that is the element iodine. Prior to an international standardization of element symbols, the symbol for this element in German was "J" (note that other annotations on this image are also in German). It's also a match based on its atomic weight and its location on the periodic table by adjacency to other elements. DMacks (talk) 21:37, 8 June 2018 (UTC)

Former Christians tag
The article references indicate not only was he a Christian but remained in the Orthodox Church until he died. Some may say he was or was not very devout. That doesn't make him a "former Christian", so the tag is inappropriate. — Preceding unsigned comment added by 73.38.0.54 (talk) 04:04, 10 April 2020 (UTC)
 * The article makes the claim that "His son would later inform that he departed from the Church and embraced a form of "romanticized deism".[22]" When I look at the cited source in the footnote, it is the son who claims his father departed from the church, but the part about "romanticized deism" is commentary from the book's author, not from the son. Perhaps a more correct way to write the sentence would be: His son would later inform that he departed from the Church and, according to one of his biographies, embraced a form of "romanticized deism"Penguino35 (talk) 15:20, 25 June 2020 (UTC)

Which 8 elements did he predict?
The intro says that "He used the Periodic Law ... to predict the properties of eight elements that were yet to be discovered", but the article does not specify which eight. The Periodic Table section does specify three as ekasilicon (now Ge), ekaaluminium (now Ga) and ekaboron (now Sc). The See also section leads to the article Mendeleev's predicted elements, which adds ekamanganese (now Tc) clearly to the list and mentions a few others in passing but it is not clear which are included in the eight. The infobox has a figure of Mendeleev's 1871 table with about 20 blank lines for extra elements, but which did Mendeleev actually mention?

Could someone add an explicit list of the eight elements which Mendeleev actually predicted? Dirac66 (talk) 18:38, 17 April 2021 (UTC)

Semi-protected edit request on 12 November 2021
In popular culture: Dmitri Mendeleev is portrayed in the Russian 2021 Netflix movie [|Silver Skates] as an independent, wise and somewhat wild character. He stands in stark contrast to the restrictive Russian University establishment. It is due to his recognized brilliance and statue that he is able to lend support to the heroine in her quest to become the first female in the university. Slairy (talk) 20:07, 12 November 2021 (UTC)
 * Red information icon with gradient background.svg Not done: please provide reliable sources that support the change you want to be made. There should be secondary coverage of this if it is WP:DUE, especially as there is no In popular culture section. ScottishFinnishRadish (talk) 20:12, 12 November 2021 (UTC)

Alleged far sight
In view of the difficulty the table had in classifying Cobalt, Nickel, Argon, Potassium, Tellurium and Iodine, the claim to far sight is wrong. 2A00:23C4:7C8E:7100:BC2C:5FA2:2AE8:6815 (talk) 16:39, 5 August 2022 (UTC)
 * The peacock wording should be taken out. — Preceding unsigned comment added by 2A00:23C4:7C8E:7100:BC2C:5FA2:2AE8:6815 (talk) 16:42, 5 August 2022 (UTC)
 * The word "sophisticated" appears lower down, about the Sanskrit grammarians. It has to go. — Preceding unsigned comment added by 2A00:23C4:7C8E:7100:BC2C:5FA2:2AE8:6815 (talk) 16:46, 5 August 2022 (UTC)

Garbled reference(s)
The following two references (currently numbers 33 and 34) "The Soviet Review Translations" Summer 1967. Vol. VIII, No. 2, M.E. Sharpe, Incorporated, p. 38 Myron E. Sharpe, (1967). "Soviet Psychology". Volume 5, p. 30. are garbled (Sharpe is the editor and publisher of the journal, not the author). They should be deleted and replaced with the following reference (which should also replace reference 49 of the current version of the article): Kedrov, B. M. (1967) "On the Question of the Psychology of Scientific Creativity (On the Occasion of the Discovery by D. I. Mendeleev of the Periodic Law)," The Soviet Review 8(2): 26-45; translated from the original article Kedrov, B. M. (1957) Voprosy psikhologii 3(6): 91-113. https://www.tandfonline.com/doi/pdf/10.2753/RSS1061-1428080226 https://web.archive.org/web/20140418233759/http://digitalcollections.library.cmu.edu/awweb/awarchive?type=file&item=33706 192.17.85.116 (talk) 18:31, 15 March 2023 (UTC)

Claim of it coming to him in a dream
Seems like it might not be so? From the abstract of two articles from Springer in 2001 --

From [1] - "Mendeleev's dream of the periodic table of elements in its completed form is apparently specious, despite repeated citations. Not only is there no dream report but evidence rests on a colleague's second-hand account. Kedrov's examination of archival material indicates (1) that Mendeleev had already discovered the periodic table before the alleged dream took place; and (2) that a dream quite plausibly occurred somewhat later that depicted an improved representation of the periodic table."

From [2] "All accounts of this event agree that he'd worked for years on the Table, produced other drafts, but that he attributed the version he was most satisfied with to a dream. It is less clear whether Kedrov is correct in his reconstruction that it was the reversal of columns vs. rows which the dream provided."

Seems like they both reference a "Kedrov". According to [3] that's Bonifaty Kedrov who doesn't seem to be mentioned anywhere in the article or have any mention of his work on Mendeleev in his article. -- "B. M. Kedrov (1903–1985) was a pioneering historian on the origin of Mendeleev’s discovery. Kedrov discovered Mendeleev’s archived materials related to his first periodic table (dated February 17, 1869) at the Mendeleev Museum in the St. Petersburg State Museum at the end of the 1940s. He then began full-fledged research on Mendeleev’s discovery of the periodic law, which culminated in the publication of The Day of a Great Discovery (Kedrov 1958) and other books which are generally reliable resources (Mendeleev and Kedrov 1958, 1960). In his meticulous reconstruction of Mendeleev’s compilation of the first periodic table, Kedrov emphasized the “one-day discovery” (February 17, 1869), and paid only scant attention to both Mendeleev’s earlier works and the social context of the discovery. At about the same time, R. B. Dobrotin analyzed Mendeleev’s earliest works, especially those of the 1850s, and argued that essential elements of the future periodic system already existed (Dobrotin 1953; Shchukarev and Dobrotin 1954). However, Kedrov’s version of the discovery had a dominant influence on Soviet history of science. In the 1970s, A. A. Makarenya cautiously expressed some doubts about Kedrov’s description of Mendeleev’s scientific works (Makarenya 1972). After Kedrov’s death, D. N. Trifonov proposed in 1990 “Version-2” of the discovery and criticized Kedrov’s “one-day version” (Trifonov 1990). Starting from a critical reevaluation of Kedrov’s research, very different reconstructions have recently been proposed."

I don't feel like I'm in a good position to judge what's true here / don't have much experience editing wikipedia, so I thought I'd put this information in the talk page and maybe things will sort themselves out as time goes on.

[1] https://link.springer.com/article/10.1023/A:1009484504919 (archived) -- Baylor, G.W. What Do We Really Know About Mendeleev's Dream of the Periodic Table? A Note on Dreams of Scientific Problem Solving. Dreaming 11, 89–92 (2001). https://doi.org/10.1023/A:1009484504919

[2] https://link.springer.com/article/10.1023/A:1009436621758 (archived) -- Barrett, D. Comment on Baylor: A Note About Dreams of Scientific Problem Solving. Dreaming 11, 93–95 (2001). https://doi.org/10.1023/A:1009436621758

[3] https://academic.oup.com/book/40685/chapter-abstract/348382201 (archived) Kaji, Masanori, 'The Origin of Mendeleev’s Discovery of the Periodic System', in Eric Scerri, and Guillermo Restrepo (eds), Mendeleev to Oganesson: A Multidisciplinary Perspective on the Periodic Table (New York, 2018; online edn, Oxford Academic, 12 Nov. 2020), https://doi.org/10.1093/oso/9780190668532.003.0015, accessed 14 July 2023. Raphaelrk (talk) 00:54, 15 July 2023 (UTC)