Berzelian formulae

The kinds of terms in a Berzelian formula are in a one-to-one correspondence with the kinds of atoms of the substance represented. When there are no numbers in the Berzelian formula, then a different atom is signified by each term and the terms, themselves, are in a one-to-one correspondence with the atoms represented. Some have suggested that this one-to-one correspondence might make these representations pictorial, i.e., pictures of the substances represented (see Klein et al. 2003 see also Klein 2001). 

However, ordinary lists are often in a one-to-one correspondence with the different parts of what is represented as, for example, in the case of a fist of the states of a country or of the groceries brought home from the supermarket. Therefore, if the one-to-one correspondence displayed by a Berzelian formula were sufficient to make it a picture of the substance represented, an ordinary fist (and perhaps some sentences) would be pictorial, too. But we don t usually think that an ordinary list is a picture. 

Dalton s diagrams also display a one-to-one correspondence between atoms and their representations which, because the diagrams use no numbers, is always displayed. Interestingly, Dalton s diagrams seem to be unarguably pictures of the molecules they represent, whereas Berzelian formulas do not. A salient property of Dalton s diagrams, more or less absent in Berzelian formulas, is that they display the spatial relations,... 

For the distinction between Dalton s physical atomism and chemical atomism, see Rocke [1984]. For the introduction, meanings, and uses of Berzelian formulae, see Klein [2003a]. 

Klein U (2001) Berzelian formulas as paper tools in early nineteenth century chemistry. Eound Chem 3 7-32... 

The tenn paper tool as well as similar ones like conceptual tools, tools o( representation, and tool-box of science, have begun to creep into the literature, especially in the history of science. The first of these terms, papa tools, was coined by Ursula Klein (Klein, Berzelian Formulas ). The other terms I mention, which evoke similar ideas have been used by the likes of Bruno Latour, Jed Buchwald and Nancy Cartwright in spite of their widely diverging philosophical orientations. In addition terms like tools of representation are sometimes used by scientists, in particular in the computational sciences. Since one theme of this volume is paper tools in chemistry and other experimental science I will try to say a few words about how I interpret this phrase. 

Klein, U. Berzelian Formulas as Paper Tools in Early Nineteenth-Century Chemistry. Foundations of Chemistry no. 1 (2001) 7-32,... 

Dalton s diagrams were revolutionary in his time because of the direct spatial correspondence between the relative positions of the circles on the page and the relative positions of the atoms in the molecule represented. In this chapter, the section on Dalton s Diagrams explains Dalton s system and shows how this kind of representation differs from others, such as Berzelian chemical formulas. 

There were, of course, middle positions between ontological realism and extreme conventionalism or positivism. Berzelius devised the alphanumeric system which, in slightly modified form, chemists still use today in order to designate the presumed atomistic compositions of molecular formulas rather than to make any detailed statement about the nature of the atoms themselves. Each of Berzelius s letters, such as the three entities in his preferred water formula, H2O, might reasonably be taken to refer to a quantity of matter, the real micro-characteristics of which were deliberately elided. A Berzelian chemical (as opposed to physical) atom, by this more cautious interpretation, was simply a packet of elemental matter of a certain relative weight, a packet that... 

Kolbe had been a student of Wohler and Bunsen, both Berzelians, but unlike them was passionately interested in chemical theory, especially the quest to determine molecular "constitutions" (identification of the particular radicals that combine to form a given molecule). He had imbued Frankland with the same passion, contrary to the positivistic tenor of the day. Kolbe and Frankland thought that this work strongly supported the Berzelian copula formulas in which they expressed their reactions. 

Due to the recent discoveries of the rare-earth elements, most of their chemical and physical properties were stUl shrouded in mist at the beginning of 1869, and Mendeleev had to manage with the limited information he had at his disposal. At the time, Mendeleev stUl adhered to the old Berzelian atomic weights for the rare-earth elements. Not one of these values corresponded to the real atomic weights however, as they were based on the erroneous assumption that most rare-earth elements were bivalent instead of trivalent Their oxides were thus represented by the formula RO (with the higher oxide of cerium denoted as R2O3). 

Based on comparative quantitative analyses, the theory of chemical portions, and the use of Berzelian chemical formulae, attempts to create a new taxonomic system of... 

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