The intricate folds at the back of the train are kept in place by a series of tapes which the lady's maid would have tied to create the waterfall effect.
This is the underneath of the train showing the stitched dust ruffle since cleaning as we know it didn't exist. The lace ruffle would have been removed as it got dirty but since this was a special occasion gown it would gone straight from the house into the waiting carriage.
It might not be rocket science but look at the construction of the bodice inside. The pleats and darts in place and beautifully lined. It would have been worn over a whaleboned corset. A lady would have also had small silk pads sewn under the arms of the sleeves to soak up any sweat or more delicately, dewy perspiration, to leave the garment unmarked.
No galloping around in this, no showing the girly bits getting out of the carriage a la Brittany or showing the superhold panties a la Katie Cruise. You couldn't help but be a lady wearing this but knowing me I'd have the soup in the ruffles before you could say elegance.