What did we learn about Scrooge's old boss, Mr. Fezziwig?

The Ghost and Scrooge travel to the warehouse of Scrooge's apprenticeship. Fezziwig, an old, jolly man, gives Scrooge and another worker the night off for Christmas Eve. Scrooge and his friend quickly clean up and build a cozy fire. Several more people come in and a party ensues. Scrooge enjoys himself immensely until the party ends, when he remembers he is merely revisiting the scene with the Ghost. Scrooge tells the Ghost that Fezziwig's gift of happiness to his friends far outweighs the money he spent on the party. He mentions he would like to say something to his clerk.