High tides occur where Earth is closest to the moon, the water pulled by gravity onto the land. The Earth rotates past this point once each day, but high tide occurs every 12 hours and twenty-five minutes. The other high tide occurs when furthest from the moon, water is pulled up onto land by centrifugal force. The ecotone between land and water is often waterlogged; marsh grass, sand, mussels bind themselves to each other anchoring the shifting ground. To breathe and grow, marsh grass pump air from their stems down to their roots through aerenchyma tissue.
I only spent one summer working in marshes, but I still taste the air, smell the pungent dirt, remember the feel of my leg suctioned into mud, my shoe lost to the sediment.
Sesamoid bones aren’t attached to other bones. They formed – encased in tendon, pulling and gliding – from our long history with strain, with the pain that accompanies wanting more force, more torque, more twist, more spin. Patella, pisiform, and – unnamed – the two corn-kernel bones beneath the hallux (big toe).
I haven’t been dancing much lately, and what I miss most is the rotation. Pirouette, fouetté: . The way I lose momentum when spinning, then – up on relevé, sesamoids pulling and twisting, building rotational force, and sending it across the body to continue the spin.
Building, transmitting. Potential, velocity, illusion. Enough times, and the sesamoids move into the foot’s interspaces and move bone, cause pain. But rotation: it feels like it’s possible to live forever.
Science Love Letters 