This second volume contains the further investigations of Professor Preyer on the mind of the child. The former volume contained the first and second portions, devoted respectively to the development of the senses and of the will. The present volume contains the third part, treating of the development of the intellect; and three appendixes are added containing supplementary matter.

Professor Preyer considers that the development of the power of using language is the most prominent index to the unfolding of the intellect. He differs with Professor Max Müller, however, on the question whether the operation of thinking can be carried on without the use of words (see the recent elaborate work of the latter on "The Science of Thought").

At my suggestion, the painstaking translator of this book has prepared a full conspectus, showing the results of Professor Preyer's careful observations in a chronological order, arranged by months. This considerable labor will render the book more practical, inasmuch as it will enable each reader to see at a glance the items of development of the child in the several departments brought together in epochs. This makes it possible to institute comparative observations under the guidance of Professor Preyer's method. I think that I do not exaggerate the value of this conspectus when I say that it doubles the value of the work to the reader.

William T. Harris.

Concord, Mass., November, 1888.