Complex sentence: So, Gaia provides him with a blade (a Harpe, Sickle or Scythe); and when Uranus next came to lay with Gaia, Cronus lept up into action and castrated his father, overthrowing him and driving him away forever.
Split into simpler sentences: So, Gaia provides him with a blade, (a harpe, sickle or scythe); and when Uranus next came to lay with Gaia. Cronus leapt up into action and castrated his father, overthrowing him and driving him away forever.