Dr. Hood has a second time enriched our knowledge of mental disease, as it is founded upon numbers and the reflections they suggest. His present valuable contribution to the statistics of the insane is one of a series which we hope to see emanating from the officers of our large institutions, and we entirely echo Dr. Hood's earnestly expressed hope, that the Commissioners in Lunacy will recommend an uniform plan of statistical inquiry to be adopted in our county asylums, by which the present vague and unsatisfactory information contained in their reports may be compressed into form, so as eventually to become the basis of certain knowledge upon which the diagnosis and prognosis and treatment of the insane, may be conducted with some greater degree of confidence than we at present possess.