Despite early physical infirmity, the loss of sight in one eye and a largely useless left arm, Williamson grew up in a caring and stimulating intellectual environment.

[2][3] In 1849, with the support of Thomas Graham, Williamson was appointed professor of analytical and practical chemistry at University College, London.

He regarded ethers and alcohols as substances analogous to and built up on the same type as water, and he further introduced the water-type as a widely applicable basis for the classification of chemical compounds.

At the time Japan was still a closed society; the laws of the Tokugawa Shogunate making travel to another country a capital offence.

He and his wife Catherine welcomed the group into their home, taught them English, introduced them to western society, and arranged for them to study as non-matriculated students at University College London.

[9] The Chōshū Five as they later became known all served in the Japanese government, and made significant scientific and social contributions to the modernisation of Japan.