Watch on Soap2day. This one-reel documentary is pretty much what it says in the title. Cavalrymen ride their horses, first over low hedges, then over increasingly rough terrain, until by the end they are sliding down hills to cross a stream and going into caves. The horses don't seem terribly anixous to do these things. Occasionally a rider falls off and the horse walks away, as if to say "See! I told you this wasn't a good idea."