Chaim Selig Slonimsky

by Michael Baxter

Chaim Slonimsky, the Chazas, was a man of many parts: an esteemed rabbi, a prize-winning inventor, a mathematician and astronomer praised by non-Jewish scientists and a pioneer in developing Modern Hebrew.


Born in 1810 in Bialystock, he developed a love of science and mathematics from an early age.  When he was 10, astronomers came there to observe a solar eclipse and he amazed them with his knowledge.


In 1834, he published a book on algebra in Hebrew.  Expecting that he might be criticised for writing about "foreign knowledge", or for using the holy Hebrew language for profane ideas, he obtained approval of the book from the rabbis of Vilna and Brisk.  In 1835, he published a book on comets, discussing in particular the forecast return of Halley’s Comet in that year.  When Halley’s Comet duly appeared, and everything about it in his book was proved right, his reputation grew.  The greatest astronomer of the Talmud, Mar Shmuel, said that he didn’t understand comets.  Yet here was a rabbi who did!  He wrote several more books on astronomy and mathematics, some of which went to several editions.


He was discussing ideas that had never before been described in Hebrew.  Thus, to write these books, he had to invent many new words in Hebrew.  He was one of the sources drawn on by Eliezer ben Yehuda when compiling his dictionary of Modern Hebrew, and all the words he invented are now part of the Hebrew vocabulary.


In his next book, published in 1838, he pointed out that the 19 year cycle of leap years does not exactly reflect the motion of the sun and, as a result, Pesach is slowly getting later compared with the vernal equinox.  He was of course quite correct, but some people, notably the then Lubavitcher Rebbe, Menachem Mendel, were outraged at the idea that there could be anything wrong with such a key aspect of Jewish law.  After that, he was viewed with great suspicion in some quarters; it was suggested that he was corrupting people by introducing them to modern science that was not in the spirit of the Torah.


In 1842, he invented a mechanical calculator.  It won a prize of 2,500 roubles from the St. Petersburg Academy of Sciences.  While such machines had been around since the 17th Century, they had been mainly curiosities used for display purposes, rather than for actual use.  Slonimsky made them a practical proposition.


In 1844 he published a formula to calculate the type of any Jewish year.  This article was written in German, and appeared in a respected journal that regularly published papers by leading scientists and mathematicians, probably something never done before or since by a Charedi rabbi.  This gained him a reputation among non-Jewish mathematicians.  As people who have heard some of my previous talks will know, this sort of calculation is quite tricky.  Slonimsky's formula is a masterpiece of conciseness.  It is very difficult to use by hand, so maybe he invented it to boost sales of his calculator.


In 1852, he published a whole book on the calendar.  In 1853 he invented a chemical process for plating iron with lead to stop it rusting.  In 1856 he invented an improved system for sending telegrams.


While visiting Berlin in 1858 he met the scientist and explorer Alexander Von Humboldt, who praised his work and presented him to the King.  When Humboldt died the following year, Slonimsky wrote a book about him that sold well.


In 1862 he founded a weekly magazine "Hatsefirah", the first Hebrew organ devoted mainly to science.  It closed after a few months due to his many other commitments, but he started it again in 1874.


Probably his most controversial publication was an article in Hatsefirah that he wrote at the age of 81.  He said that the miracle of the Chanukah oil had been misinterpreted, and pointed out that the Rambam does not mention it.  He thought that the Hasmoneans had only used 1/8 of the limited supply of oil each day, so that the Menorah had not burned continuously but only for a few hours. This is entirely in keeping with the Rambam's view of miracles as not being supernatural.  The then Lubavitcher Rebbe (Sholom Dov Ber, not the man who had criticised him 50 years earlier) condemned the article, and his Chassidim wrote two whole books attacking it.  Slonimsky had his defenders, and the controversy went on for years.


He died in Warsaw in 1904, at the age of 94, and a street was named after him.


But that is not the end of the story.  Nearly fifty years later, he became a player in a Cold War controversy.  In 1952, Stalin recalled how Slonimsky had made major improvements to telegraph systems.  This was received with scorn in the USA, where many people automatically rejected any suggestion that Russians had anticipated Americans in anything and assumed that Thomas Edison had made the improvement due to Slonimsky.  The New York Times even claimed that Stalin had invented him.  Fortunately for Slonimsky’s reputation, his grandson, Nicolas Slonimsky, had emigrated to the USA and become a celebrated musicologist.  He wrote an indignant letter to The New York Times, rebutting the suggestion that his grandfather did not exist.  And so half a century after his death, this remarkable man finally became known to the Western world.

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