translation.en: It's just a small cylinder down here which holds the generator inside and all the linkage and it's the hot cap -- the hot cylinder on the top -- this part gets hot, this part is cool, and electricity comes out.
translation.zh: 这下面有个小的缸体， 里面是所有的零件和发生器 这里是热端--顶部的热的活塞== 这个部分变热，这个部分温度较低， 可以输出电能。