A study was made of the flotation of very dilute solutions of two cationic collectors, hexadecyltrimethylammonium chloride (HTMAC) and dodecyl-pyridinium chloride (DPC), in the presence of added electrolytes. The concentration, charge, and nature of these electrolytes were found to have a pronounced effect on the rates of flotation. The determinations were made at two different gas flow-rates; unexpectedly, the ratios of the flotation rates were found to be different to the total surface areas of the bubbles passing.