The Complete Works in Philosophy, Politics and Morals of the late Dr. Benjamin Franklin, [Vol 2 of 3]

Read at the Royal Society, June 3, 1756. The particles of air are kept at a distance from each other by their mutual repulsion. Every three particles, mutually and equally repelling each other, must form an equilateral triangle. All the particles of air gravitate towards the earth, which gravitation compresses them, and shortens the sides of the triangles, otherwise their mutual repellency would force them to greater distances from each other. Whatever particles of other matter (not endued with that repellency) are supported in air, must adhere to the particles of air, and be supported by them; for in the vacancies there is nothing they can rest on. Air and water mutually attract each other. Hence water will dissolve in air, as salt in water.