Henry's law deals with the solubility of gases. The solubility of a gas in a solvent is directly proportional to the partial pressure of the gas in contact with the solution.

The Bends is a disease in which dissolved nitrogen concentrations become very large at the increased pressures found in great depths of water. When the external pressure is reduced, the solubility is lowered, gaseous nitrogen emerges from the dissolved states, and the gas bubbles cause innumerable physiological problems.