by, as we term them, spiritual agencies, exterior to themselves. Others, again, owe their sufferings to a mixed condition. The interior sense, it is true, is opened; but it has been and continues open by the action of disease. This form of disease may, in one sense, be compared to the loss of the scarf-skin, and a consequent exposure of surfaces for whose excessive sensitiveness, nature has provided a muffling. The loss of this covering is attended by an habitual impassability, by influences against which we were intended to be guarded. But in the case of the brain, and the nerves immediately connected with its functions and its sensuous impressions, the cerebral circulation undergoes periodically that vibratory disturbance, which, I believe, I have satisfactorily examined and demonstrated, in my MS. Essay, A. 17. This vibratory disturbance differs, as I there prove, essentially from the congestive distur-
