Complex sentence: Teddy sends Gander to fetch some water for tea, but the only source turns out to be a water crane on the platform, where Gander finds the old bridge wheel, which is chained and padlocked.
Split into simpler sentences: Teddy sends Gander to fetch some water for tea, but the only source turns out to be a water crane on the platform. While procuring the water, Gander finds the old bridge wheel, which is chained and padlocked.