A split infinitive construction denotes a particular type of syntactic tmesis in which a word or phrase, especially an adverb, occurs between the infinitive marker to and the infinitive of the verb. Although rare from a statistical viewpoint, the earliest instances of the split infinitive date back to the 13th century, in which a personal pronoun, an adverb or two or more words could appear in such environments (Visser 1984, II: 1038-1045). Its use drops drastically throughout the 16th century, but it begins to gain ground again in the 19th century, hence resisting the severe criticisms of grammarians. Nowadays, however, a search for these types of constructions in a present-day English corpus reveals that the prejudice against split infinitives is receding. Therefore, this paper investigates the actual use of the construction in different corpora with the following objectives: a) to provide the statistics of the construction from a historical perspective; b) to analyse the type of adverbs occurring in these contexts; c) to offer a taxonomy of the adverb from a functional perspective; d) to investigate the combined effect of stress and rhythm in the development of the construction; and e) to review the actual use of a prototype splitting in present-day English usage.