Genre:

Essay, Drollery

Relevant illustrations:

wdct. [4]

Subjects:

Light, Physics

    Explains that since light is 'from its name, without weight' it 'travels with a velocity which renders it uncommonly warm when it reaches us'. Suggests various amusing experiments to test dispersion, refraction and other properties of light. For example, to prove dispersion it suggests punching somebody in the eye and noting that 'a curious dispersion of light immediately ensues, showing various lights of startling brilliancy, and leaving a ring of prismatic colours round' the eye. Warns that pencils of light 'must not be confounded with lead pencils', which produce 'shade', and that although reflection 'is best explained by reference to a glass [...] two or more glasses tend to diminish reflection'.