How did Cannizzaro explain differences between alkali metals and alkaline-earth metals?

Stanislao Cannizzaro addressed the confusion surrounding the formulas for compounds of alkali metals and alkaline-earth metals in his 1858 pamphlet, Sunto di un corso di filosofia chimica.

Prior to his work, many chemists sought to assign these metals to the same formula type due to their striking chemical analogies. Cannizzaro argued that this approach was problematic and that placing these metals into different categories was necessary. He demonstrated that distinguishing between them helped eliminate certain anomalies when using their physical properties to deduce atomic weights. By applying Amedeo Avogadro's theory, Cannizzaro provided a consistent theoretical structure that resolved these classification issues and helped establish a single, reliable system of atomic formulas.1