LIGHT filters of coloured glass and gelatin are in common use for visual and photoelectric photometers. They are satisfactory, on the whole; but the glass filters are easily broken, and those of ...

PERSPEX, the acrylic sheet product which changed the world, has been manufactured in Darwen for nearly 70 years — and still is.

The Western Australian Museum has been accused of glorifying vandalism after it acquired a piece of clear perspex that once protected an iconic Australian painting which was graffitied by climate ...