1828, Samuel Frederick Gray, The Operative Chemist, page 499:
Blue lights, or blue fire, is a preparation in which zinc and sulphur, or sulphur alone, are used. The particular colour is communicated by the zinc and sulphur.
1874, Marcus Clarke, For the Term of his Natural Life, Penguin, published 2009, page 57:
The blue-light, which, at its first flashing over the ocean, had made the very stars pale their lustre, and lighted up with ghastly radiance the enormous vault of heaven, was now only a point […].
2015, Mark K. Ragan, quoting Robert Fleming, Proceedings of a Naval Court of Inquiry into the Sinking of the Housatonic, 1864, quoted in Confederate Saboteurs, Texas A&M University Press, →ISBN, page 98:
When the 'Canandaigua' got astern, and was lying athwart, of the 'Housatonic,' about four ship lengths off, while I was in the fore rigging, I saw a blue light on the water just ahead of the 'Canandaigua,' and on the starboard quarter of the 'Housatonic.'
2019 October, Roger Ford, “Power failure highlights specification confusion”, in Modern Railways, page 26:
Blue-light escorts were provided where possible to get engineers to the stranded GTR trains to reset the software.
Used other than figuratively or idiomatically:seeblue,light.
Usage notes
The original chemical mixtures burned with a blue flame. Later versions omitted any colouring agents, producing a bright white light, but retained the name by convention.
2011, John Donoghue, Police, Crime & 999, Troubador Publishing, →ISBN:
When we weren't blue lighting, we had to obey the 30 mph limit, but out of town we had a training exemption from any speed regulations and were encouraged to push the car to its limits... and we did.
2012, Jon Mukand, The Man with the Bionic Brain, Chicago Review Press, →ISBN:
They jumped into his cruiser and blue-lighted it to Boston Medical Center at eighty miles per hour.
2014, James Rennie, The Operators, Pen and Sword, →ISBN:
Roger that. Feds and green army are blue lighting to you.