ABSTRACT
Rainwater in uninhabited regions or lakes in high-altitude glaciated areas may be nearly pure water with a little dissolved carbon dioxide; rivers and intermediate lakes contain more solutes derived from the rocks and soil over which the water has passed; saline ponds in desert areas where stream water evaporates may be saturated with minerals containing calcium carbonate, sodium carbonate, calcium sulfate, and sodium chloride. Far exceeding all these varied types of water in total amount, the oceans contain substantial concentrations of solutes but are remarkably uniform in composition throughout the world.
