Demonstrations included the production and examination of the properties of hydrogen, oxygen, nitrogen and carbon dioxide gases.

An electrolysis cell is demonstrated, first in the electroplating of platinum conductors by dissolved copper, then the production of hydrogen and oxygen gases and their recombination to form water.

[3]According to Frank Wilczek: It is a wonderful laying-bare of surprising facts and intricate structure in a (superficially) familiar process — the burning of a candle.

I think it exhibits a marvellously creative mind at work on its home ground, poking into details and following peculiarities to their root with carefully crafted experiments.

[4]According to Bill Griffith, F.R.S.C., of Imperial College London: Faraday uses the candle as a symbol to talk about the nature of combustion — how the oxygen from air is needed, how water and CO2 are produced and the hidden role of hydrogen.