The closest thing you are going to find these days to the kind of saddle they would have used in 18th England is a cutback saddle or a dressage saddle - not a hunt seat jumping saddle which is the most common type of "english" saddle you will see today. Try this link for examples http://www.frontierequestrian.com/getProduct.cfm?CatList=15 The first and last saddles on that page are pretty close to the images/drawings I've seen of 19th century english saddles.

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