We cannot but be greateful for the publication of this work and the translator's skill, who has so ably rendered the remarks and conversations of the children into childish colloquialisms, for placing at the disposal of all who are interested in the subject of child psychology the rich and valuable material it affords, in the many actual conversations of the two little boys as well as numberless other remarks and questions of other children. At the same time we cannot help some feeling of disappointment that this data has not been turned to still better account.