a word employed by Mr Brougham to denote a property of light which causes the different rays to be acted upon by bodies, and to begin to be refracted, reflected, inflected, and deflected, at different distances. This property follows the same law that the other optical properties of light follow: the red ray having most reflexity, and the violet least (See Philosophical Transactions, 1797, p. 360.) Mr Brougham has denoted this property by the three words, refractivity, reflexity, and flexity; but as the power is the same, there is no occasion for different names. Some philosophers have refused to admit this as a new property; we have not verified it by experiment.