In maritime law . Any atmospheric condition (including not only fog properly socalled, but also mist or falling snow) which thickens the air, obstructs the view, and soIncreases the perils of navigation . Flint & P. M. R. Co. v. Marine Ins. Co. (C. C.) 71 Fed.210; Dolner v. The Monticello, 7 Fed. Cas. 859.