In 1704, Isaac Newton published his "treatise on the reflexions, refractions, inflexions and colours of light". Within the pages he described many experiments and observations of the interaction of light with refractive materials, and ultimately proposed his theory of light as 'corpuscular' (made of particles) One of the key aspects of his studies was the diffraction or 'inflexion' of white light into constituent 'pigments' or colours. Hence the title of this collection.