This material we obtain through the channels of the senses, and then store in that wonderful storehouse, the Memory, from whence we bring out material from time to time, which we proceed to weave into the fabric of Thought. The skill of the worker depends upon his training, and his ability to select and combine the proper materials. And the acquiring of good materials to be stored up is an important part of the work.
A mind without stored-up material of impressions and experiences would be like a factory without material. The machinery would have nothing upon which to work, and the shop would be idle. As Helmholtz has said, “Apprehension by the senses supplies directly or indirectly, the material of all human knowledge, or at least the stimulus necessary to develop every inborn faculty of the mind.” And Herbert Spencer, has this to say of this phase of the subject, “It is almost a truism to say that in proportion to the numerousness of the objects that can be distinguished, and in proportion to the variety of coexistences and sequences that can be severally responded to, must be the number and rapidity and variety of the changes within the organism—must be the amount of vitality.”
A little reflection upon this subject will show us that the greater degree of exercise and training given the senses, the greater the degree of mental power and capability. As we store our mental storehouse with the materials to be manufactured into thought, so is the quality and quantity of the fabric produced.
It therefore behooves us to awaken from our “lazy” condition of mind, and to proceed to develop our organs of sense, and their attendant mechanism, as by doing so we increase our capacity for thought and knowledge.
Before passing to the exercises, however, it may be well to give a hasty passing glance at the several senses, and their peculiarities.
The sense of Touch is the simplest and primal sense. Long before the lower forms of life had developed the higher senses, they had evidenced the sense of Touch or Feeling. Without this sense they would have been unable to have found their food, or to receive and respond to outside impressions. In the early forms of life it was exercised equally by all parts of the body, although in the higher forms this sense has become somewhat localized, as certain parts of the body are far more sensitive than are others. The skin is the seat of the sense of Touch, and its nerves are distributed over the entire area of the skin. The hand, and particularly the fingers, and their tips, are the principal organs of this sense.
The acuteness of Touch varies materially in different parts of the body. Experiments have shown that a pair of compasses would register impressions as a very slight distance apart when applied to the tip of the tongue. The distance at which the two points could be distinguished from one point, on the tip of the tongue, was called “one line.” Using this “line” as a standard, it was found that the palmar surface of the third finger registered 2 lines; the surface of the lips 4 lines, and the skin of the back, and on the middle of the arm or thigh, as high as 60 lines The degree of sensitiveness to Touch varies greatly with different individuals, some having a very fine sense of touch in their fingers, while others manifested a very much lower degree.