div class=ts-pagebuttonPage 1button div class=ts-image amp-img class=ts-thumb alt=Page 1: The Theory of Heat src=https:reader035vdocumentsusreader035viewer2022080320575067c51a28ab0f07ad1420html5thumbnails1jpg width=142 height=106 layout=responsive amp-img divp© 1929 Nature Publishing Grouppdiv