Two recent investigations, both motivated by studies of Landau damping, are reported. With the aid of observations from the N.E.R.C. network phase differences between stations have been studied. Clear results were obtained more easily than expected. East-west phase differences were rather small. The possibility of deducing the flow of micropulsation energy across L shells from ground data is discussed and it is shown that tilts of the polarization ellipse are significant. Field line resonance is important and theoretical models are briefly discussed.