In the story, a businessman hears an account from a man who has devoted years attempting to make synthetic diamonds, only to end as a desperate outcast.
Wells's story appeared a few years after the claims of James Ballantyne Hannay in 1879 and Henri Moissan in 1893, that they had made artificial diamonds.
Others tried to repeat this experiment in later years, with only a few reporting that they could reproduce the result; commercially successful production of synthetic diamonds was not achieved until the 1950s.
[2][3] The narrator is getting relief from his business life by gazing at the river from the Thames Embankment near Temple (Essex Street is mentioned, and there is a view of Waterloo Bridge and the towers of Westminster beyond).
He finally succeeded when, using an idea suggested by experiments of Gabriel Auguste Daubrée, he put the mixture which might produce diamonds together with dynamite in a cylinder too strong to burst.