Having now shown, 1st, That judicious mental exercise promotes the development of the cerebral organs in youth; 2dly, That there is strong presumptive evidence in proof of the same effect taking place even in mature age; 3dly, That we are still little acquainted with other important physiological conditions which act powerfully in modifying the results of exercise; and 4thly, That the knowledge of these conditions would greatly extend the efficacy of moral and intellectual education, and multiply our means of advancing the moral welfare and happiness of the race; I do not require to add another word to induce phrenologists to collect additional evidence on all the doubtful points, and to prosecute the enquiry with persevering accuracy, and with a constant view to its important practical advantage. [1] “Principles of Physiology,” &c. 5th edit. p. 292, &c. [2] See “The Physiology of Digestion considered with Relation to the Principles of Dietetics.” Second edition, p. 198. We have selected the above article from the “Edinburgh Phrenological Journal” for the purpose of calling the attention of phrenologists in this country to the important principles which it contains. The article comes from the pen of a gentleman who probably understands the physiology of the brain, and its real functions, better than any other man living. It is unnecessary for us to dwell on the importance of correctly understanding the above principles, as connected with phrenology, and the desirableness of collecting additional evidence, in order to elucidate them, and show their numerous applications to the various duties and pursuits of life. We would therefore solicit for publication in this Journal, facts showing the positive increase, either in _size_ or _activity_, of any particular organ or organs; and also communications tending to illustrate and establish more fully the truth of the enquiries proposed by Dr. Combe, respecting the true physiological laws of the brain.—ED. ARTICLE V. PHRENOLOGICAL DEVELOPMENTS AND CHARACTER OF WILLIAM MILLER, WHO WAS EXECUTED AT WILLIAMSPORT, PA., JULY 27TH, 1838, FOR THE MURDER OF SOLOMON HOFFMAN. MR. EDITOR,—