(_In alarm, rising, as Knox purses his lips to bid them enter._) Don't let anybody in. I don't want to be seen here--with you. Besides, my presence will not put you in a good light. {Knox} (_Also rising, starting toward door._) What I do is always open to the world. I see no one whom I should not permit the world to know I saw. (_Knox starts toward door to open it._) (_Hubbabd, looking about him in alarm, flees across stage and into bedroom, closing the door. During all the following scene, Hubbard, from time to time, opens door, and peers out at what is going on._) {Knox} (_Opening door, and recoiling._) Margaret! Mrs. Chalmers! (_Margaret enters, followed by Tommy and Linda. Margaret is in evening dress covered by evening cloak._) {Margaret} (_Shaking hands with Knox._) Forgive me, but I had to see you. I could not get you on the telephone. I called and called, and the best I could do was to get the wrong number. {Knox} (_Recovering from his astonishment._) Yes. I am glad. (_Seeing Tommy._) Hello, Tommy. (_Knox holds out his hand, and Tommy shakes it gravely. Linda stays in back-ground. Her face is troubled._) {Tommy} How do you do? {Margaret} There was no other way, and it was so necessary for me to warn you. I brought Tommy and Linda along to chaperon me. (_She looks curiously around room, specially indicating filing cabinets and the stacks of government reports on table._) Your laboratory. {Knox} Ah, if I were only as great a sociological wizard as Edison is a wizard in physical sciences. {Margaret} But you are. You labor more mightily than you admit--or dare to think. Oh, I know you--better than you do yourself. {Tommy} Do you read all those books? {Knox} Yes, I am still going to school and studying hard. What are you going to study to be when you grow up? (_Tommy meditates but does not answer._) President of these great United States? {Tommy} (_Shaking his head._) Father says the President doesn't amount to much. {Knox} Not a Lincoln? (_Tommy is in doubt._) {Margaret} But don't you remember what a great good man Lincoln was? You remember I told you? {Tommy} (_Shaking his head slowly._) But I don't want to be killed.--I'll tell you what! {Knox} What? {Tommy} I want to be a senator like father. He makes them dance. (_Margaret is shocked, and Knox's eyes twinkle._) {Knox} Makes whom dance? {Tommy} (_Puzzled._) I don't know. (_With added confidence._) But he makes them dance just the same. (_Margaret makes a signal to Linda to take Tommy across the room._) {Linda} (_Starting to cross stage to left._) Come, Tommy. Let us look out of the window. {Tommy} I'd rather talk with Mr. Knox. {Margaret} Please do, Tommy. Mamma wants to talk to Mr. Knox. (_Tommy yields, and crosses to right, where he joins Linda in looking out of the window._) {Margaret} You might ask me to take a seat {Knox} Oh! I beg pardon.