rapidity with which he worked his "Adam's apple" up and down. He then asked if there was any danger. I answered him that there was none, except to those who were troubled with heart-disease. He immediately put his hand up over his heart and said, "Well, my heart is quite seriously affected," but by that time we had secured the necessary pressure to enable me to open the diving door at the bottom, so I released the "locking dogs" and allowed the door to open, and when he saw the water did not come in, his face cleared and he said, "Well, you know I never would have believed it if I had not seen it," and then he added that he would not have missed seeing it for the world. Another interesting incident in connection with undergoing pressure occurred while at Hampton Roads, Va. One day I received a visit from a professor of mathematics and his wife at the Hampton Institute, each of whom held a professorship in the college. They stated that the _Argonaut_ had been discussed before the faculty and that they would like very much to go down in her and see the diving door opened, which I was very glad to show them. Just previous to going into the diving compartment Professor S---- explained to me that his wife was deaf in one ear, that she had been under a physician's care for about two years, and he wanted to know if undergoing pressure was likely to have an injurious effect upon her. Not being a physician or knowing what might occur, I advised against her undergoing pressure; but she insisted on going into the compartment, promising that if she felt any ill effect from the air pressure she would tell me and I could let her out. I was reluctant to have her go in, and when we entered the compartment I allowed the air to come in very slowly, in the meantime giving a general description of the vessel, and occupying as long a time in the procedure as possible. I noticed almost at once that she was in pain. Although she turned her back to me, I could tell by her clenched jaws and hands that she was probably suffering agony. I then stopped the pressure and suggested to the professor that he had better let his wife go out, but through clenched teeth she still protested, "No, go ahead; I can stand it!" Finally we got the pressure on and opened the door, but, while the professor seemed delighted, his wife made no remark. She simply stood with her hands clenched and I was afraid she was going to faint. Then all at once she screamed; but immediately after her face lighted up with a smile and she exclaimed, "It is all gone!" When she came out of the compartment, after the experiment was over, I noticed her put her hand up to one ear, and she said to her husband, "Do you know, I can hear as plainly out of that ear as I ever could!" About a year afterward I saw Professor S---- and he told me that apparently the experiment had cured his wife of deafness where physicians had failed to help her; that to date it had never returned, and that she could hear as well as she