13. It is easy to midjudge numbers where intricate movement is concerned, but there could have been no less, and probably many more, than a hundred Martins weaving a pattern of great beauty and subtlety, and above all, unity. It was a single ever changing pattern carried on in complete silence. I tried to capture a single bird with my binoculars to make identification certain, but rarely succeeded. Momentarily I assessed as many Sand as House Martins, relatively small, in batlike flight, but it was hard to clinch the issue. There was no question of writing a note, and I cannot remember now whether I considered Swifts or Swallows in the reckoning. It is of no account. It was one of those occasions when wonder takes over, and aesthetic enjoyment overrides scientific accuracy. I felt myself becoming caught up in it all, visually and mentally weaving with the birds, yet so earthbound, so utterly clumsy and rooted. More than once I felt sufficiently dizzy to be obliged to lower my glasses and regain two-legged balance lest I should be enticed to an undignified belly-flop into the marsh at my feet. I was no longer detached as an observer, but involved as a would-be parti- cipator . My time was up, but not before a strange thing happened to underline the theme of participation. I realised that some of the birds, as their flight brought them momen- tarily near me, were approaching closer than they had at the beginning. A few more