Light is made up of certain little balls, which rebound from what is solid, and return obliquely; but pass thro' what admits of an entrance in a right line, as air or glass: so that what makes the moon enlighten us, is, that she is a firm and solid body, from which the little balls rebound.

Conversations on the Plurality of Worlds, The Second Evening (pp. 45-46), Printed for Peter Wilson. Dublin, Ireland. 1761