Monochromatic lamps and filtered spectra Sir John Musgrave Eighteen swan marks issued by

Eighteen swan marks issued by the Crown to landowners in the county of Lincolnshire

The byline reads 'The Dawn of a New Motoring Era'

Sheriff 1837-8 standing in ceremonial robes

Architectural details from the Promoter Life Insurance Company's offices

Monochromatic lamps and filtered spectra Sir John Musgrave Eighteen swan marks issued byFigures showing monochromatic lamps fuelled by alcohol diluted in water to produce a yellow flame (figures 1 3), with views of the effects on the spectrum created by filtering light through various types of coloured glass (figure 4 numbers 1 16). Plate 28 from the paper 'Description of a monochromatic lamp for microscopical purposes, &c. with remarks on the absorption of the prismatic rays by coloured media.', by David Brewster, originally published