Suppose the writer of a billet, the contents of which are known only to himself, lets it out of his hands and loses sight of it for five minutes, it may be carried either in the direct sunlight, or into electric or magnesium light, and be read by the aid of the egg-glass. The placing of a piece of cartridge paper in the envelope, or the coloring of it black, is a means of defense at hand. In their present form, telegrams cannot be protected from perusal, unless delivered at once into the hands of the addressees. A few tests employed by mind readers and clairvoyants, so called from their presumed ability to read other people’s minds, will, I think, prove interesting. Let us suppose the performer, as a means of proving his ability to cause his subject to read his mind from a distance, or by mental telegraphy, execute the following feat. His subject, let us say his wife, is at home. The professor is in a public place, a store, or banking house, etc. He requests some one to write a question; he hands this person a fountain pen and a pad of paper. After the person has done so, he is requested to fold the communication up, place it in an envelope and seal it, and then put it in his pocket. He is now asked to write a letter or note to the professor’s assistant, asking her to inform him what it was that he had asked on the paper inclosed in the envelope in his pocket. This note, and the pen also, for fear the lady has no writing utensils, is carried by the gentleman himself to the lady. She reads the request, and, turning the paper over, she writes the answer correctly on the other side. Sometimes, instead of the gentleman himself going with the note, a messenger boy is sent with it and the answer brought back by him. In either case the paper and pen are sent along. The pen is an ordinary fountain pen, and it is by means of it that the lady receives the desired information of what has been written. First the professor has to know what has been written. He simply says to the gentleman: “You must allow me to read the question; for, if I do not see it, how can my assistant see it, for it is through me she is enabled to know? What I see I convey to her by mental telegraphy, and thus convey the communication.” After the professor sees the communication he goes to a desk and gets an envelope, or takes one out of his pocket, and gives it to the gentleman to place his question in and seal it. While this is being done he stealthily writes on a piece of fine, thin paper an exact copy of the question. This he makes into a little pellet and places it in the little cap or end that is made to cover the point of the pen for protection. Of course it is now easy to see the method by which the question is made known to the assistant. She has simply to remove the pellet of paper, unfold it and read it. Sometimes a pad of paper is used that has cunningly concealed between two of its leaves, near the top, a piece of carbon duplicating paper.