DR HAVARD: All conductors of all sizes. Vibration relates to tension and it relates to length. Where we have conductor spans of comparable length - and now I am talking about those that go across fjords in Norway where they can be up to five kilometres long, there is frequently a damping system added to the middle of the span, as well as damping at the ends. So this particular span, if it had been in the company I work for in Ontario Hydro, we would have added what we call a wave trap in the middle. Lines of this size that go across rivers, for example, would have extra dampers at mid-span to trap waves because the benefit of dampers is limited. It has a length component to it. So in the middle of the span we would put a pair of dampers. Those would be, in that case, Stockbridge dampers but they are located at a particular separation so they are effected at all frequencies. That is a practice that is a standard practice in most utilities. While I mention damping again, the bridging conductor is also a damper. There were talks about whether it was responding to Aeolian vibration and it oscillates at its own natural frequencies. It's a very low tension element and you can just twang this one and you can see that it will vibrate at its own natural frequencies and at those frequencies it's acting as a damper.