Technikatörténeti szemle 22. (1996)

Papers from the Second International Conference on the History of Chemistry and Chemical Industry (Eger, Hungary, 16–19 August, 1995) - Lichocka, Halina: The Methodological Problems of Organis Chemistry in the First Half of the 19th Century – Jedrzej Sniadeckis work

Already in the 1850s many more artificially obtained organic substances were known than substances found in nature. Researchers were also increasingly successful in synthesizing new preparations with properties analogous to those found in natural products obtained from plants. "From malic acid and ammonia, one can artificially obtain aspartic acid, derived naturally from aspargine"

13

, wrote Justus Liebig in his New Letters on Chemistry. The experiments by Wurtz and Hoffman, conducted even earlier than Liebig publicized his views, showed that by replacing in ammonia all three atoms of hydrogen with organic groups, one could obtain alkali that showed the properties of ammonia and were quite similar to quinine and morphine. The discoveries in the field of organic synthesis were indeed multiplying at very fast rate. All is One Jedrzej Sniadecki's famous statement that "life in nutritive matter consists in the permanent transformation of form and in a given form in the permanent transformation of matter"

14 was the result of speculations on the circulation of matter in nature. Sniadecki pointed out that minaral substances assimilated by plants were transformed into organic substances, which could subsequently serve as food for animals and undergo further transformations in physiological processes. The end-point of the cycle was their decomposition and return to an inorganic form, wherefrom the cycle could start anew. The idea of a permanent transformation of matter led to the concept of the unity of "the building stuff" of all living organisms and that part of inanimate nature that Sniadecki called nutritive matter. Hence the notion of a ceaseless circulation of matter was constantly present in views on nature. In Liebig's textbook, for example, it was formulated in the following way: "carbon, which is found in the seeds and fruits of plants in the form of oil and fat, was previously a component part of the air, and the plant accepted it in the form of carbonic acid. Its change into fat took place thanks to a vital plant force, with a contribution from light."

15 Liebig went even further in his generalizations on the animate world, for he saw unity not only in the qualitative composition, but also in the continuity of structure. "We encounter no hiatus in the infinite sequence of compounds, beginning from the substances that plants feed on, i.e. carbonic acid, ammonia and water, all the way up to the parts of the brain, the most complex in an animal body"

16

, he claimed. This was an idea which followed directly from the views espoused by the Swiss naturalist of the Enlightenment, Charles Bonnet, especially in his famous book on nature: Contemplation de la Nature (with editions in 1764,