[3] Brunel’s winning design for a bridge across the Avon Gorge differed from Guppy's patent in several significant ways: it had a deck suspended from flat wrought iron bar links rather than resting on top of chains like Guppy's; and it did not feature riverbed foundations (a key component of Guppy's design) as it was constructed 75 metres above high tide where the piers were not at risk of damage from water erosion.