association neurones and transmit the nervous current from sensory areas to motor areas or from one sensory area to another.  For example, suppose you see a brick falling from above and you dodge quickly back.  The neural action accompanying this occurrence consists of an impression upon the nerve-cells in the eye, the conduction of the nervous current back to the visual area of the brain, the transmission of the current over association neurones to the motor area, then its transmission over the motor neurones, down the spinal cord, to the muscles that enable you to dodge the missile.  The association neurones have the further function of connecting one sensory area in the brain with another.  For example, when you see, smell, taste and touch an orange, the corresponding areas in the brain act in conjunction and are associated by means of the association neurones connecting them.  The association neurones play a large part in the securing and organizing of knowledge.  They are very important in study, for all learning consists in building up associations.

From the foregoing description we see that the nervous system consists merely of a mechanism for the reception and transmission of incoming messages and their transformation into outgoing messages which produce movement.  The brain is the center where such transformations are made, being a sort of central switchboard which permits the sense-organs to come into communication with muscles.  It is also the instrument by means of which the impressions from the various senses can be united and experience can be unified.  The brain serves further as the medium whereby impressions once made can be retained.  That is, it is the great organ of memory.  Hence we see that it is to this organ we must look for the performance of the activities necessary to study.  Everything that enters it produces some modification within it.  Education consists in a process of undergoing a selected group of experiences of such a nature as to leave beneficial results in the brain.  By means of the changes made there, the individual is able better to adjust himself to new situations.  For when the individual enters the world, he is not prepared to meet many situations; only a few of the neural connections are made and he is able to perform only a meagre number of simple acts, such as breathing, crying, digestion.  The pathways for complex acts, such as speaking English or French, or writing, are not formed at birth but must be built up within the life-time of the individual.  It is the process of building them up that we call education.  This process is a physical feat involving the production of changes in physical material in the brain.  Study involves the overcoming of resistance in the nervous system.  That is why it is so hard.  In your early school-days, when you set about laboriously learning the multiplication table, your unwilling protests were wrung because you were being compelled to force the nervous current through new pathways,