One is that he observed when people were machining cannon barrels, a lot of heat was generated, and there was a lot of work done.

第一种说法说焦耳发现,制作加农炮筒时，会产生大量的热，同时这中间有大量的做功。

麻省理工公开课 - 热力学与动力学课程节选

So in principle, if I measure how much hotter, I can determine how much heat was produced, and from that, I should be able H to calculate delta H at T1.

所以原则上，如果我测量，变热了多少，我就能确定，有多少热被产生,从中我就可以计算T1下的Δ

麻省理工公开课 - 热力学与动力学课程节选