He employed (what is now known as) Aitken's delta-squared acceleration process in his calculation of Pi, thought to be the earliest use of this series acceleration method (the modern method was introduced by Aitken in 1926).
本計算ではエイトケン加速を用いており、世界的にみても数値的加速法のもっとも早い適用例の一つである（エイトケンによる導入は1926年）。