too commonplace to deserve a moment of our attention, and which we are, nevertheless, utterly unable to understand. In a crude way we can understand the machinery of sound waves. We can see the action of the vocal organs, by means of which they are produced. We can learn something of the nerve fibers of the ear upon which these sound waves fall. But what else is there at the two ends of this line of action? What is there within these two masses of matter, which enables either one of them to hold wireless communication with the other?
Let us assume that we are wholly familiar with the motion of each molecule of air involved in the sound waves; that we are able to make drawings of all the delicate modulations of muscular motion which are involved when the organs of speech produce these sound waves. Our drawings are to show precisely how these motions of the vocal organs are different, when English words are spoken with Irish and with German accent. Our knowledge is to be similarly complete concerning the receiving apparatus at the hearing end of the line. We trace these motions finally along nerves leading to two brains at opposite ends of the line. We may assume that we know all of these structures and their motions in the most minute detail. What do we then know of the phenomenon that one conscious being, embodied in a mass of matter, may determine or influence the thoughts and actions of another conscious being, by formulating thoughts in words, and delivering them to him through the air? How are we to explain the fact that he can plan and deliver a sentence, which will, unknown to the receiver, change the frequency of bis heart beats?
He may even do this by sending to him through the mails a sheet of paper upon which he has made certain marks in ink. On the enclosing wrapper are certain other marks, images of which, by means of ether waves, are formed on the retinal membranes of clerks in the post office. By such means the muscular motions of these clerks are determined. The letter is delivered to the particular person whom the sender had in mind.
When the receiver of this paper has also allowed ether waves from these ink marks and the paper which bears them, to fall upon the nerves of his retinal membranes, he knows the mental attitude of the man who sent that paper. He makes some computations. He does some thinking. And, by the way, what is doing some thinking? He makes a response to the wireless message. The result is a mental agreement between two minds. A check and a deed of transfer of title to property are drawn, and are exchanged, and a family moves from one house to another.
What would the former cave dweller think of these amazing phenomena? I venture to assert that this transaction is vastly more complex than any electrical action. The man who talks of the mysteries of
