- "'Coffee Pot' is just a nickname for an engine with a boiler that points up in the air, like those things people make coffee in."
- ―Edward, The Adventure Begins
The "Coffee Pots" were four small engines that worked for the Tidmouth, Knapford and Elsbridge Railway.
Bio in the Railway Series
The "Coffee Pots" were constructed and designed at Tidmouth by a young Sir Topham Hatt when he was an engineer to the Tidmouth, Knapford and Elsbridge Railway. They were designed as four small 0-4-0 tank engines with vertical boilers that were nicknamed "Coffee Pots". This was partly due to the fact they resembled coffee pots, and they were prone to cough up dirty brown water.
The Tidmouth, Knapford and Elsbridge Railway eventually became part of the North Western Railway. With the formation of the new main line these engines were relegated to only operated between Elsbridge and the east side of the bay platform at Knapford. Between 1924-5 the branch line was extended to Ffarquhar and Anopha Quarry, but these engines were not deemed adequate for the haul and after a probationary period at Wellsworth, Thomas was transferred to take charge of their branch line. The "Coffee Pots" continued to serve the line as back up, though their limited braking abilities on the steep Quarry Tramroad sometimes caused the heavy stone trains to run out of control.
The "Coffee Pots" were withdrawn from service and were eventually scrapped. They were not very well documented, and were never even photographed but reference is made to them by Ffarquhar's Station Master, Kevin Volley. In his letter it is revealed one or another were still operating during the event of Thomas and his crew being fined for illegally operating on the tramroad extension. Their actual scrapping date is not mentioned but their remaining importance would have been further diminished when Toby arrived in 1951 and took over the quarry's operations.
Bio in the television series
Glynn the "Coffee Pot" was the original No. 1 engine on the North Western Railway and he used to work on the Ffarquhar branch line with some other "Coffee Pots". By the time Thomas had arrived, Glynn was the only remaining one, the others presumably scrapped. Glynn was eventually restored many years later and moved to the Ulfstead Castle Estate Railway.
- The Coffee Pots were the first Railway Series-exclusive engines to either appear physically or be mentioned in the television series since the Diesel in the fourth season. They, including Glynn, were brought into official canon by Railway Consultant Sam Wilkinson.