Paper, 'A discourse on this problem why bodys, dissolved in menstrua specifically lighter then themselves, swim therein' by William Molyneux Molyneux discusses how heavy materials, such as iron or mercury, can float in the lighter solvent they have been dissolved in, and how this relates to the law of hydrostatics. Subject: Hydrostatics Read to the Royal Society on 5 May 1686 Published in Philosophica Transactions as 'A discourse on this problem; why bodies dissolved in the menstrua specifically lighter than themselves, swim therein' 1686