In Chapter 56, we read that Lady C's "horses were post" when she arrived at Longbourn to see Lizzy. The notes in my book say that means they were supplied by post-stations for general hire. How were horses managed in this era? Presumably people left their homes with their own horses. If there came a point in a journey where it was necessary to change horses, were their own stock stabled at the inn (or wherever you changed horses?) and collect them, refreshed, on the return journey? Perhaps Lady C arrived with the horses she did because her own horses were worn out by being pushed to get to Longbourn as quickly as possible!