Both the story of the discovery of the periodic law and the key role played in that discovery by the 19th-century Russian chemist, Dmitri Ivanovich Mendeleev (1834 - 1907) are well-known and need not be repeated here.
However, given that the periodic law currently enjoys a status in chemistry not unlike that of the theory of evolution in biology, it is rather curious that so far no attempt has been made to provide an English-language collection of Mendeleev's most important writings on this subject.Now that I have read the first three papers, I understand why. Smile. Wow. Long paragraphs. Long sentences. Dry.
Being "dry" in the original is fine. He was a chemist. But one would expect that the editor's notes could have livened up the reading.
I will slog on, to complete the book. Perhaps it will get better.
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"In 1868, Mendeleev began writing his famous textbook, Principles of Chemistry. As he later related, it was while exploring various alternative organizational schemes for this book that he hit upon the periodic law. While waiting for the book to appear in print (the first edition was published in installments between 1868 and 1871), Mendeleev produced a single-page flier summarizing his new organizational scheme.
The flier was entitled: An Attempted System of the Elements Based on their Atomic Weights and Chemical Analogies.
He circulated the paper among Russian chemists in early 1969.
In March, 1969, he presented a more detailed paper to the newly founded Russian Chemical Society. The paper was actually read by the Russian chemist, Nikolai Menshutkin; Mendeleev was ill at the time. [I graduated from high school in 1969, exactly 100 years later; it would have been nice had our chemistry instructor, for whom I had great admiration and respect, noted this. I think it would have left an impression on us.]
This detailed paper, in turn, was published in the first volume of the society's new journal and appears in English translation as paper 2 of this collection."
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Some notes may be posted here.
The discovery of gallium by Lecoz de Boisbaudran, 1875, sparked a great interest in the periodic law among French chemists..... p. 13.
Mendeleev began to work on his papers in which he described his periodic law in 1868 and published his findings in the landmark paper in 1871. I graduated from high school in 1969, almost exactly one hundred years after his discovery.
"As these disputes (between the Russians and Germans working on the "periodic table") show, almost from the beginning, the literature on the periodical law was marred by a widespread failure to distinguish between the periodic law, on the one hand, and the periodic table, on the other -- a confusion which persists in the historical literature even to this day." -- p. 111, introduction to papers 4 - 8.
"In 1869, I announced the following law, called periodic: 'The properties of simple substances, the constitution of their combinations, as well as the properties of the latter, are periodic functions of the atomic weights of the elements.'" -- p. 135, the sixth paper.
It is incredible how much they knew and how many elements had been discovered by the late 1800s. It is also amazing how important Mendeleev's periodic law was in predicting new elements. It really is quite an amazing story.
"The periodic law requires changes in the atomic weights of many elements as yet incompletely examined -- for example, indium, cerium, yttrium, erbium, didymium, etc. Before the existence of this law, there was no reason for doubting the generally accepted atomic weights of these elements. Now that the researches of .... and others have led to the same conclusion as that which is derived from the periodic law, it becomes incontestable that the law shows us the truth, which is in fact its support." -- p. 139, the seventh paper.
"The periodic law has, for the first time, provided us not only with a means of predicting unknown elements, but also of determining the chemical and physical properties of simple bodies yet to be discovered, as well as those of their compounds. The discovery of gallium by Lecoq de Boisbaudran, whom I now have the honor of counting as a friend, may be considered as the initiation of the periodic law and reckoned amongst the most brilliant pages in the annals of science....It must be admitted that, prior to the periodic law, there was no possibility of a similar prediction." -- p. 139, the seventh paper.
There are certain examples that Mendeleev repeats many times. He was very proud of his law, and particularly proud that the discovery of three elements predicted by him and his periodic law were discovered in his lifetime, and had the properties he predicted:
- Gallium, Ga - discovered in France, 1875, by Lecoq de Boisbaudran; the metal was the eka-aluminum Meneleev predicted
- Scandium, Sc - discovered in Sweden, 1879, by Nilson; extracted from the rare earths of the cerite group; the metal was the eka-boron he had predicted
- Germanium, Ge - discovered in Germany, 1886, by Cl. Winkler; extracted from the mineral argyrodite from Freiberg in Saxony; the metal was the eka-silicon Mendeleev had predicted
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