One of the most widespread and fascinating phenomena to be found on the cliff face of the outer beach is what I call sand-leaves, or sand-pseudopods. These are distinct, ropy strands of sand and clay that flow down the face of the cliff and expand at the bottom into a bulbous, organic shape. Eerily organic in appearance, these leaves of sand can form almost anywhere and at any time of the year, though they are most common on uniformly sandy scarps interrupted by horizontal clay layers.
One of the best places from which to observe these leaves of sand is on the stretch of beach from Long Nook to Highland Light in Truro. One morning, after a recent storm, I visited that beach. The surf, all milky and glassy, was still massive. It slid over itself on the lower beach in great foamy slabs, like ice on a hot stove, leaving gray and rainbow-colored scarves of foam on the sand with no more substance than smoke.
The lower two-thirds of the cliff face were looped with great ropey pseudopods of flowing clay and sand. They were over a hundred feet long in most places and less than a foot across, except where they widened at the bottom in a breast-like shape, giving the appearance of enormous pendulous dugs. Sometimes the lower curved loops of the sand pods were edged with small dark stones or pebbles, like an exquisite necklace laid upon a smooth mounded bosom.These narrow rivers of sand emerged from a horizontal clay layer in the cliff, flowing down to the base, and in places even out onto the upper beach. In shape and texture they had the appearance of braided protoplasmic extensions of nerve cells, or as if an enormous sand plant were sending its rootlets down into the cliff face. They were a dramatic example of how the inanimate here mimics, and often surpasses, the inanimate.
I can never observe these sandy pseudopods without thinking of Thoreau. Although he never mentions them in his book Cape Cod he observed the same phenomenon in his hometown in Concord, where it, in fact, becomes the thematic and symbolic climax of his great work, Walden.
In the penultimate chapter of that book, titled “Spring,” Thoreau writes: “Few phenomena gave me more delight than to observe the forms which thawing sand and clay assume in flowing down the sides of a steep cut on the railroad through which I passed on my way to the village…The material was sand of every degree and fineness and of various rich colors, commonly mixed with a little clay…The whole bank, which is from twenty to forty feet high, is sometimes overlaid with a mass of this kind of foliage, or sandy rupture, for a quarter of a mile on one or both side.”
He could well be describing the sand pseudopods, or leaves of sand, on the cliff face of the Outer Beach. And as he meditates on these flowing forms of sand and clay he eventually concludes that “There is nothing inorganic” in Nature…The earth is not a mere fragment of dead history, stratum upon stratum like the leaves of a book, to be studied by geologists and antiquarians chiefly, but poetry like the leaves of a tree.”
You can see these leaves of sand for yourself – almost anywhere, any time on the Outer Beach. For me at least, it adds to their fascination to know that Thoreau found in this same ordinary, commonplace natural phenomenon evidence that the world is universally alive, healthy, and perennially new.
