The Determination of Atomic Weights

It took over half a century after Dalton proposed his atomic theory of the elements for chemists to break a circularity in molecular formulae and atomic weights and establish that water is H2O and not HO, or HO2, or H4O, and so on. Their analysis employed relations of inductive support of bewildering complexity at many levels, from that of specific substances to that of general theory. Their efforts illustrate the complex, nonhierarchical character of relations of inductive support.