When we view the newly-born infant, and consider its state for many weeks after it has become a member of our community, we are then enabled to form some opinion of the almost insensible gradations, by which it acquires its perceptions. An enumeration of the progressive steps of this tardy process is within the power of any patient and accurate observer; but this detail does not constitute a part of the plan which has been adopted. It has been endeavoured by writers on this subject, to establish a distinction between perception and sensation, and the reader for his information may consult their works: they do not however appear to have founded this distinction on any obvious difference, nor to have adduced sufficient reasons for their separate establishment, as independent properties of the nerves. To feel, to experience a sensation, or to perceive, implies consciousness; it is that which is transmitted by the nerves to the sensorium, either by the organs of sense, or by the internal nerves; as pain, or feelings of which we are conscious. Consciousness is the test, the evidence, the proof of sensation or perception. This point has been adverted to, in order that terms should not be multiplied without a distinct and essential difference of meaning. The five senses, together with some auxiliaries, which will be the subjects of future notice, may be considered as the instruments or agents, by which the edifice of mind is constructed. In the act of perceiving by the different senses, there are some circumstances, which are particularly deserving of attention. In order that perception may fully and certainly take place, it is necessary that the person should be undisturbed; he ought to be exempt from external intrusions, and internal perturbation. During this process the respiration is in general more slowly drawn, the body endeavours to maintain a perfect quietude, and its position becomes fixed. When we perceive objects by the eye, this organ becomes fixed and the lips are usually closed. During our examinations by the touch, the eye is also fixed, the breathing is suspended, and the lips brought into contact: the fingers are separated, and their more delicately tangent surfaces applied to the object with their utmost expansion. In the exercise of audible perception, the neck is stretched forth, and the ear applied to the quarter from whence the sound appears to issue; the mouth is partly open to conduct the vibrations to the Eustachian tube. When we acquire intelligence by the smell, the lips are very firmly closed, the nostrils become dilated, and the inspiration of air through them is conducted by short and successive inhalations. From the connection between the smell and organs of taste, (and this association is more remarkable in some animals than in man,) it is difficult to describe the process, which, however, principally consists, when minutely tasting, in moving the tongue (the principal