A picture through the arch of the stone bridge.

May 22. 

After two or three days more of rainy weather, it is fair and warm at last. Thermometer seventy-odd degrees above zero. 

When the May storm is over, then the summer is fairly begun. 

9 a. m. — I go up the Assabet in boat to stone bridge.

Is it not summer when we do not go seeking sunny and sheltered places, but also love the wind and shade? 

As I stand on the sand-bank below the Assabet stone bridge and look up through the arch, the river makes a pretty picture. 

It is perfectly smooth above the bridge and appears two or three feet higher (it is probably half as much) than below and rushes to its fall very regularly, the bridge partially damming the stream: the smoothness extends part way under the bridge in the middle, the turbulent water rushing down each side.

H. D. Thoreau, Journal, May 22, 1857

When the May storm is over, then the summer is fairly begun. See May 22, 1858 ("Something like this annually occurs. After this May storm the sun bursts forth . . . and we seem to have taken a long stride into summer.") Also  May 17, 1853 ("Does not summer begin after the May storm?”); May 11, 1854 (" I suspect that summer weather may be always ushered in in a similar manner, — thunder-shower, rainbow, smooth water, and warm night.").

Is it not summer when we do not go seeking sunny and sheltered places, but also love the wind and shade?  See April 26, 1857 ("By and by we shall seek the shadiest and coolest place. “); May 10, 1857 ("But now at last I do not go seeking the warm, sunny, and sheltered coves; the strong wind is enlivening and agreeable.”) Compare May 22, 1854 (“I rest in the orchard, doubtful whether to sit in shade or sun.”)