Experiments are made on wave-lengths between 200 and 500 ms. for distances of transmission less than 200 kms. It is found that the variations of downcoming wave intensity are uncorrelated on two receivers separated by about one wave-length, and it is shown that this implies a considerable amount of lateral deviation of the waves. A special receiver is used to confirm the occurrence of lateral deviation, and an estimate of the angle of deviation is made. The possible causes of intensity variation are considered in the light of these experimental results, and it is suggested that a major cause of “fading” is the interference, at the ground, of waves “scattered” from a series of diffracting centres distributed over an area of radius at least 20 kms. in the present experiments. The possible results of such a mechanism are discussed.