A convenient method is described for determining the apparent density of soil aggregates down to 2 mm in diameter. The aggregates are evacuated, wetted with a non-polar liquid (kerosene), drained at a standard tension, and their volume determined by displacement in this liquid. Results obtained have shown that apparent density is measurable to within 0.03 g/c.c. or about 2 per cent. Features of this method and their significance are discussed.