Letters: September 2018

The article on the history of helium was splendid (Chemistry World, August 2018, p50). I am a retired physical chemist whose research specialty was NMR spectroscopy, so over the years have greatly valued helium as an essential superconducting magnet coolant.

There are certain aspects regarding the discovery of helium on Earth that tend to be overlooked. The person who first identified terrestrial helium was not William Ramsay but Luigi Palmieri, an Italian physicist at the University of Naples, who identified the D₃ spectral line in gas associated with lava on Mount Vesuvius. Palmieri was an expert in seismological measurements of volcanoes and reported his finding in the rather obscure publication of the Royal Academy of Naples.¹ It seems unlikely that the astronomer Norman Lockyer was aware of this observation.