When Hephaestus was born, he was ugly and weak, with a broken foot. Hera did not like the way he looked and threw him off her castle which was on top of the clouds. Hephaestus fell for one day and one night before falling into the sea. The sea animals rescued him and took him to an island called Lemnos. he made a set of golden thrones for him mother.
Hera realised her mistake of throwing Hephaestus off Mount Olympus and pleaded Zeus to welcome Hephaestus back. Hephaestus politely refused, saying that he was quite happy where he was. Then he set to work and fashioned a beautiful golden throne and sent it to Hera as a ‘thank you gift’ for the invitation. The instant she sat on it, golden ropes flew out and tied her up locking her into the chair.