I am, Gentlemen, Very truly yours, S. L. CLEMENS. Private:--I beg to apologize for my delay, gentlemen, but the card of invitation went to Elmira, N. Y. and hence has only just now reached me. This letter was not sent. He reconsidered and sent an acceptance, agreeing to speak, as the committee had requested. Certainly there was something picturesque in the idea of the Missouri private who had been chased for a rainy fortnight through the swamps of Ralls County being selected now to join in welcome to his ancient enemy. The great reunion was to be something more than a mere banquet. It would continue for several days, with processions, great assemblages, and much oratory. Mark Twain arrived in Chicago in good season to see it all. Three letters to Mrs. Clemens intimately present his experiences: his enthusiastic enjoyment and his own personal triumph. The first was probably written after the morning of his arrival. The Doctor Jackson in it was Dr. A. Reeves Jackson, the guide-dismaying “Doctor” of Innocents Abroad. ***** To Mrs. Clemens, in Hartford: PALMER HOUSE, CHICAGO, Nov. 11. Livy darling, I am getting a trifle leg-weary. Dr. Jackson called and dragged me out of bed at noon, yesterday, and then went off. I went down stairs and was introduced to some scores of people, and among them an elderly German gentleman named Raster, who said his wife owed her life to me--hurt in Chicago fire and lay menaced with death a long time, but the Innocents Abroad kept her mind in a cheerful attitude, and so, with the doctor's help for the body she pulled through.... They drove me to Dr. Jackson's and I had an hour's visit with Mrs. Jackson. Started to walk down Michigan Avenue, got a few steps on my way and met an erect, soldierly looking young gentleman who offered his hand; said, “Mr. Clemens, I believe--I wish to introduce myself--you were pointed out to me yesterday as I was driving down street--my name is Grant.” “Col. Fred Grant?” “Yes. My house is not ten steps away, and I would like you to come and have a talk and a pipe, and let me introduce my wife.” So we turned back and entered the house next to Jackson's and talked something more than an hour and smoked many pipes and had a sociable good time. His wife is very gentle and intelligent and pretty, and they have a cunning little girl nearly as big as Bay but only three years old. They wanted me to come in and spend an evening, after the banquet, with them and Gen. Grant, after this grand pow-wow is over, but I said I was going home Friday. Then they asked me to come Friday afternoon, when they and the general will receive a few friends, and I said I would. Col. Grant said he and Gen. Sherman used the Innocents Abroad as their guide book when they were on their travels.