- Doc: "Iced tea?"
- Marty: "No thanks. (pause) It's a refrigerator."
- — Doc and Marty in the livery stable
A refrigerator was built by Emmett Brown in 1885 as a way to make ice for his own drinks. Even though Doc had happily accepted his new life as a blacksmith in the Old West, this was one of the 20th century amenities he couldn't live without.
The large, noisy, steam-powered machine took up an entire wall of Doc's livery stable. While Marty McFly was in discussion with him, the machine's steam whistle blew and Marty was instructed to turn a valve. Out of a spout on the machine came a single brownish ice cube, which Doc then dropped into his beaker of tea.