There is one sylph for each type of gas thus an oxygen sylph, a nitrogen sylph, a hydrogen sylph, a nitrous oxide sylph, a carbon dioxide sylph, a carbon monoxide sylph, and so on.
I think, but do not know, that sylphs govern the rules by which we get wind or breezes, air flow, turbulence, lift in airplanes and weather patterns [up to a point] high and low air pressures. There is probably an interaction between the systems of the salamanders [fire systems] and the gas systems. As 'light' produces warmth and it is warmth that causes differences in air temperatures and movements of air, mathematically the existence of these processes is known scientifically – but not expressed by meteorologists in precise terms.
In olden days people saw these spirits when they inhaled smoke, the fumes from incense, or smoke from pipes etc. The term Sylph (also called sylphid) originates in Paracelsus, who describes sylphs as invisible beings of the air, elementals of air. They were also known as Ariels.
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- Blithe spirit - Thought palaces in pink and gold
- Evans-Wentz, W Y - Alchemical and Mystical Theory 
- Frost, Robert - When I was young, we dwelt in a vale
- Ibn El-Arabi - The Tarjuman al-Ashwaq - Halt at the abodes and weep over the ruins
- Keightley, Thomas - Stromkarl
- Keightley, Thomas - The Elle woman
- Mare, Walter de la - The Spirit of Air
- Millais, John Everett - Ferdinand lured by Ariel
- Morrells, Luce and the moving wall
- Paracelsus - extract from Scritti alchemici e magici
- Scotland, Barra - The Testimony of John Campbell
- Steiner, Rudolf - Gnomes, Undines, Sylphs and Salamanders
- Steiner, Rudolf - Nature spirits - Lunar Pitris
- Steiner, Rudolf - Nature spirits - Sylphs