Here’s a research project for anyone who wants to take it on:
As early as 1833 [sic*], Konstantin Tsiolkovsky had calculated that a rocket would work in the vacuum of space. The man was a visionary, detailing many of the requirements of the space-age which would only begin to take shape decades later. In 1895 he published an article postulating space travel as a possibility and in 1898 published findings that were to be of the greatest importance: namely that liquid propellants would be more efficient than solid propellants and that of these, a mixture of either oxygen and hydrogen or of oxygen and kerosene, would be most suitable for rocket engines. (Dark Moon: Apollo and the Whistle-Blowers, Mary Bennett and David S. Percy, page 134)
Obviously, since the topic has come up so often in the comments here, I an interested in the first sentence more than anything. A research project like this would imply that access to Tsiolkovsky’s 1833 work would be necessary.
* Tsiolkovsky was born in 1887. I suggest this year should be 1883.