But it was the next evening that the celebration rose to a climax.  This was at the grand banquet at the Palmer House, where six hundred guests sat down to dinner and Grant himself spoke, and Logan and Hurlbut, and Vilas and Woodford and Pope, fifteen in all, including Robert G. Ingersoll and Mark Twain.  Chicago has never known a greater event than that dinner, for there has never been a time since when those great soldiers and citizens could have been gathered there.

To Howells Clemens wrote: 

Imagine what it was like to see a bullet-shredded old battle-flag reverently unfolded to the gaze of a thousand middle-aged soldiers, most of whom hadn’t seen it since they saw it advancing over victorious fields when they were in their prime.  And imagine what it was like when Grant, their first commander, stepped into view while they were still going mad over the flag, and then right in the midst of it all somebody struck up “When we were marching through Georgia.”  Well, you should have heard the thousand voices lift that chorus and seen the tears stream down.  If I live a hundred years I sha’n’t ever forget these things, nor be able to talk about them.  I sha’n’t ever forget that I saw Phil Sheridan, with martial cloak and plumed chapeau, riding his big black horse in the midst of his own cannon; by all odds the superbest figure of a soldier.  I ever looked upon!  Grand times, my boy, grand times!

Mark Twain declared afterward that he listened to four speeches that night which he would remember as long as he lived.  One of them was by Emory Storrs, another by General Vilas, another by Logan, and the last and greatest by Robert Ingersoll, whose eloquence swept the house like a flame.  The Howells letter continues: 

I doubt if America has ever seen anything quite equal to it; I am well satisfied I shall not live to see its equal again.  How pale those speeches are in print, but how radiant, how full of color, how blinding they were in the delivery!  Bob Ingersoll’s music will sing through my memory always as the divinest that ever enchanted my ears.  And I shall always see him, as he stood that night on a dinner-table, under the flash of lights and banners, in the midst of seven hundred frantic shouters, the most beautiful human creature that ever lived.  “They fought, that a mother might own her child.”  The words look like any other print, but, Lord bless me! he borrowed the very accent of the angel of mercy to say them in, and you should have seen that vast house rise to its feet; and you should have heard the hurricane that followed.  That’s the only test!  People may shout, clap their hands, stamp, wave their napkins, but none but the master can make them get up on their feet.

Clemens’s own speech came last.  He had been placed at the end to hold the house.  He was preceded by a dull speaker, and his heart sank, for it was two o’clock and the diners were weary and sleepy, and the dreary speech had made them unresponsive.