TY - JOUR T1 - On the Chief Line in the Spectrum of the Nebulae JF - Proceedings of the Royal Society of London (1854-1905) VL - 49 SP - 399 EP - 403 PY - 1890/01/01/ UR - http://dx.doi.org/10.1098/rspl.1890.0107 M3 - doi:10.1098/rspl.1890.0107 AU - Keeler, J. ER -