George Carlin was not only an icon as a comedian, he was a hit with the pre-school generation of the day.

He portrayed Mr. Conductor in the children's hit series "Shining Time Station ' 1991 to 1993 and was also the narrator for the American version of "Thomas The Tank Engine".

Mr. Conductor II

The second Mr. Conductor, played by George Carlin and starring in Shining Time Station seasons three, four, the family specials and Mr. Conductor's Thomas Tales, was the American cousin of the first. When compared to the original, this Mr. Conductor had a more brightly-colored outfit, and more-known sense of humor; as he is occasionally seen playing tricks on Schemer. (This is most likely due to the fact that the actor, George Carlin, was a comedian.) In a few cases, after some gold dust landed on a drawing of him, an evil twin was created, who caused trouble at the station, and could only be turned back into a picture by using magic dust or glue. For a brief time after the series ended, Mr. Conductor hosted a series called Mr. Conductor's Thomas Tales.

Unlike the past Mr. Conductor (Ringo Starr) and the future Mr. Conductor (Alec Baldwin), he was the only one out of the three who had a deeper-pitched whistle that sounded more like an actual train whistle, which was altered further during the TV Specials, and Mr. Conductor's Thomas Tales.

From Wikipedia

We still have all the old videos to enjoy Mr. Carlin's antics with Thomas. He was a favorite with the toddler and pre-school kids at our house.

He will be missed.