The large ventricles of the brain are the chambers into which liquids flow from the spaces between the tissues, and from elsewhere, as is known. Thus they are, so to speak, the urinary bladders of the brain, where fluid, or lymph, is mingled with [animate] spirit and whence in turn, [animate] spirit and better elements are secreted, one after the other. * 829 is placed after 826, following the author's instructions.