In modern English the infinitive with _to_ is used as a verbal substantive. When we say, “I wish you to do this,” “you are able to do this,” we can still perceive the datival function of the infinitive. Likewise in such phrases, “it is time,” “it is proper,” “it is wrong to do that,” _to do_ may still be felt as an oblique case. But we have only to invert these sentences, and say, “to do this is wrong,” and we have a new substantive in the nom. sing., just as in the Greek τὸ λέγειν. Expressions like _for to do_, show that the simple _to_ was not always felt to be sufficiently expressive to convey the meaning of an original dative. WORKS ON THE INFINITIVE. The infinitive has formed the subject of many learned treatises. I divide them into two classes, those which appeared before and after Wilhelm’s excellent essay, written in Latin, “De Infinitivi Vi et Natura,” 1868; and in a new and improved edition, “De Infinitivo Linguarum Sanscritæ, Bactricæ, Persicæ, Græcæ, Oscæ, Umbricæ, Latinæ, Goticæ, forma et usu,” Isenaci, 1873. In this essay the evidence supplied by the Veda was for the first time fully collected, and the whole question of the nature of the infinitive placed in its true historical light. Before Wilhelm the more important works were Hofer’s book, “Vom Infinitiv, besonders im Sanskrit,” Berlin, 1840; Bopp’s paragraphs in his “Comparative Grammar;” Humboldt’s paper, in Schlegel’s “Indische Bibliothek” (II. 74), 1824; and his posthumous paper in Kuhn’s “Zeitschrift” (II. 245), 1853; some dissertations by L. Meyer, Merguet, and Golenski. Benfey’s “Sanskrit Grammar” (1852), too, ought to be mentioned, as having laid the first solid foundations for this and all other branches of grammatical research, as far as Sanskrit is concerned. After Wilhelm the same subject has been treated with great independence by Ludwig, “Der Infinitif im Veda,” 1871, and again “Agglutination oder Adaptation,” 1873; and also by Jolly, “Geschichte des Infinitivs,” 1873. I had myself discussed some questions connected with the nature of the infinitive in my “Lectures on the Science of Language,” vol. ii. p. 15 seq., and I had pointed out in Kuhn’s “Zeitschrift,” XV. 215 (1866) the great importance of the Vedic +vayodhai+ for unraveling the formation of Greek infinitives in σ-θαι. THE INFINITIVE IN BENGALI.