Following the estimation of the state of the blood comes naturally that of the state of the circulation; and for the purpose of the alienist the efficiency with which the peripheral circulation is carried on is the main thing to be determined. From his point of view it is of far less importance to discover an insufficiency of the mitral valve than to find a cold blue flabby hand or nose; for a damaged valve is consistent with an efficient supply of blood to the highest nervous centres; but if one part of the peripheral circulation is seen to be badly carried on, the inference is unavoidable that the circulation in other peripheral regions is similarly defective. The direct evidence of the condition of the cerebral circulation obtainable by the ophthalmoscope should not be neglected. Although the “heat of the head” is a matter of prime importance among the laity, and is commonly considered by physicians as of some value, yet, having regard to the fact that the whole of the face and scalp are supplied by branches of the external carotid artery, while the encephalon receives its blood mainly from the internal carotid, I was for some time doubtful whether much stress should be laid on this external temperature. I have, however, seen a case in which not only did the head sweat freely, but steam rose visibly for many consecutive hours from the scalp of a woman lying in a well-warmed ward, and without any fluid or medicament being applied to the head. In that case there was found after death the most excessive congestion of the whole cerebral substance.