After Bertha had passed through we were treated to s couple of hours of fine weather. At this time of year one of the delights it to watch dragonflies hawking along the hedges. This is a Migrant Hawker, taking a rest from chasing smaller insects to rest in the sunshine. The structure of a dragonflies wings is a truly remarkable wonder of nature. This species has a wing span of around 8.5 cm, while the largest species in Britain, the Emperor Dragonfly has a wingspan of 10.6 cm. These are pretty large insects, but around 300 million years ago Meganeura monyi had a span of 65cm. The gigantic size of these insects is way beyond what seems to be theoretically possible but may have be feasible if the atmosphere had higher oxygen levels than are present now.