Tidelines

Every twelve hours or so

 the sea reaches its highest point

 then ebbs back, 

pulling away 

from the line that marks high tide. 

Sometimes, several tides in a row

 are lower than those previous, 

and you can see 

a series of lines 

that show the high water mark. 

This line is traced by shells and sticks, 

or sometimes 

you can simply see 

that the sand looks slightly different, 

more packed down, 

or rippled in a different pattern. 

As you walk across these tidelines 

it is as though you are travelling through time. 

Like sawing through the rings of winter's passage 

that circle the trunk of a century old maple, 

or snow-blowing along a wall of white, 

revealing the layers of icy snow 

compacted over the winter. 

Or like an archeologist 

reading history 

from stratifications 

in the earth's crust on the wall of a quarry. 

The tidelines 

show the days that have passed by, 

maybe the last days of summer. 

And then 

a really high tide will rise above them all and start the patterns all over again.