Riddle me this... What has two hands, is wound tight, and has a lot of ticks?

猜个谜...什么东西有两只手，紧紧缠绕，嘀嗒不停？

So riddle me this, though, Clara: How can we travel into the past?

不过，克莱拉，请给我一个谜语：我们怎样才能回到过去呢？