Plate, spectral tubes and spectroscope by [Jul Scheuren] Figures 1-3 showing the design and form of spectral tubes for enclosing gas used in Plucker and Hittorf's experiments and the arrangement of the spectral tubes in relation to the spectroscope. Subject: Physics / Chemistry Published in Philosophical Transactions as 'On the spectra of ignited gases and vapours, with especial regard to the different spectra of the same elementary gaseous substance'. Received by the Royal Society on 23 February 1864. Read 3 March 1864. [1864]