THE importance of air photography for the archæologist cannot be exaggerated. Not only does it permit accurate plotting of the visible monuments of an area to be made when detailed maps of the district are inaccurate or non-existent, but further it frequently indicates where ancient monuments now disappeared had once stood. Let us suppose a building, say, a Roman villa, once occupied an area of ground. Where the foundations had been dug the soil would have been disturbed, and, though perhaps nothing is visible now above ground, below the soil much brickwork, etc., would still occur. Corn or other crops on the field where the villa had been would grow somewhat differently as to height and density where the foundations lie, and would thus mark out as it were on a plan where they were. On the ground nothing can be seen ; from the air the whole is clearly set out. Messrs. Kodak are to be congratulated on the exhibition of such photographs which has been arranged at their premises in Regent Street, London, and is open to the public until July 21. An excellent explanatory pamphlet by Dr. J. K. St. Joseph, illustrated by a number of actual air photographs, has been issued. There are also maps showing where the various sites appearing in the exhibition occur. Such well-known localities as Stonehenge and Avebury have been included.