A Jorge Luis Borges parody lifted off my hard disk...

According to 'a certain Chinese encyclopedia,' the Celestial Emporium of Benevolent Knowledge, railway rolling stock may be categorised as follows:

• Stock used to transport the Emperor.
• Scrapped stock.
• Stock suitable for branch lines.
• The stock you rode in last week.
• Stock that reminds you of your first train ride.
• Stock that foamers foam over.
• Stock running on foreign gauges.
• Stock not included in this list.
• Stock you have forgot about.
• Stock for carrying goods.
• Stock too light for today's jobs.
• Somebody else's stock.
• Stock that has just derailed.
• Stock too far away to tell what it is.