hiː bᵻlˈiːvd ðætðə hˈiːt pɹədˈuːst ɪnðə hˈɑːɹt kˈɔːzd blˈʌd tə ɹɪˈækt ɪn ɐ sˈɪmɪlɚ wˈeɪ tə bˈɔɪlɪŋ, ɛkspˈændɪŋ ˈaʊt θɹuː ðə blˈʌd vˈɛsəlz wɪð ˈɛvɹi bˈiːt.
He believed that the heat produced in the heart caused blood to react in a similar way to boiling, expanding out through the blood vessels with every beat.