Or, Vertebral Palpation is the name given the manual examination of spinal vertebrae. General Propositions Every palpation should be made with the adjustment of the vertebrae in mind. The record of palpation should be a correct guide as to direction of adjustment. No subluxation impossible of adjustment should be recorded. The two essentials of correct palpation are _accurate perception_ and _correct reasoning_. To secure the first, a certain approved manner of using the hands is herein laid down and a considerable amount of tactile sense development by practice is required. Correct reasoning depends upon knowledge of all the important facts concerning the spine and of the rules governing palpation. Absolute concentration is required and to this end many of the following rules are directed. Habits of Palpation Every palpater unconsciously forms habits of thought and action. These habits may be good or bad. We deliberately form a habit of holding the first three fingers closely together or the habit of using a downward glide, but we should avoid the habit of finding certain subluxations because they are usual and expected rather than because they are actually there. For instance, one may easily form a habit of listing every other vertebra in the spine, his whole record thus depending upon his first choice. Because of this perfectly natural tendency to establish a routine of thought and action and to follow it precisely, it is best not to attempt palpation without the aid of an experienced teacher until after correct habits have been formed. Once formed, a palpation habit, right or wrong, is very hard to break. Many a teacher has expended himself uselessly in the effort to undo some technical fault acquired by the student in a blundering undirected trial. Facts Concerning the Spine The spinal column is composed of twenty-six segments called vertebrae, twenty-four movable and two fixed. The movable vertebrae are divided for convenience in study into three sections. There are seven Cervical vertebrae, twelve Dorsal, and five Lumbar in the normal individual. The number of Dorsals or Lumbars may vary by one in a rare case. These variations occur in about one spinal column in each five hundred and are usually in the Lumbar region, which may contain four or six vertebrae. A prominent first sacral spinous process may be mistaken for an extra Lumbar. Five vertebrae have special names. The first Cervical is called Atlas; the second Cervical, Axis; the seventh Cervical is commonly known as Vertebra Prominens on account of its long and large spinous process, although this long process belongs to the sixth Cervical or first Dorsal instead in 35% of all cases; the large, irregularly fusiform vertebra just below the Lumbars and between the ilia is called the Sacrum; and the smaller one below it, the Coccyx. The latter is occasionally missing.