This early work by Otto Jespersen was originally published in the early 20th century and we are now republishing it with a brand new introductory biography. 'Efficiency in Linguistic Change' is an informative work on linguistics and includes chapters on 'Sound-Laws', 'Semantics', 'Glottic', and much more. Otto Jespersen was born in Randers, Denmark on 16th July 1869. He worked as an academic at Copenhagen University and rose to the position of professor of English, a post he held from 1893 to 1925. Jespersen made a considerable contribution to the study of linguistics and some of his works are still used as the basic texts for study in the field.