Paper, 'An apparatus for testing the sensitiveness of safety-lamps' by Frank Clowes Clowes writes: 'It is generally acknowledged that the Davy safety-lamp cannot with certainty detect less than 3 per cent, of firedamp in the air of the mine. Gas-indicators of much greater sensitiveness have been invented; amongt these the electrical apparatus of Liveing and the spirit safety-lamp of Pieler take first rank. The objection to these special forms is, however, a serious one.' Annotations in pencil and ink. Subject: Scientific apparatus and instruments Received 4 June 1891. Read 18 June 1891. Communicated by [Henry Edward] Armstrong. A version of this paper was published in volume 50 of the Proceedings of the Royal Society as 'An apparatus for testing the sensitiveness of safety-lamps'. 1891