 Frege’s contributions were not immediately understood or appreciated, and in the closing decade of the century logic was dominated by the three volumes of Ernst Schröder’s Vorlesungen über die Algebra der Logik (1890–95). Schröder provided an encyclopedic treatment of the logical work of Boole and Peirce, systematizing and extending their results. Peirce’s quantifiers make their appearance in volume two, but the distinction between first-and second-order quantification is not drawn with comparable clarity. As Frege pointed out in his review (1895), Schröder’s notation did not distinguish set membership from the subset relation, and as a result it can be difficult to tell whether he intends a given quantification to range over the subsets of a domain (i.e., to be second-order) or over its elements (i.e., to be first-order). Schröder employs both second-order and first-order quantifications; and in his third volume he used the technique of expanding a second-order quantification into an infinite product of first-order quantifications—a technique that was a development of the Peircian product notation, and that was to furnish the starting point for the investigations of Löwenheim. But Schröder does not extract from his wider system a sub-system of first-order logic, and does not treat the distinction of orders as itself being of any great significance, either mathematically or philosophically. In this sense, he is less clear than Peirce’s paper of 1885. (A helpful analysis of Schröder’s logical work is contained in Brady 2000.)