Glass is one of the most enigmatic materials in human civilization — ubiquitous, endlessly useful, and yet still a mystery to physicists, who continue to debate its true nature.

The many uses of glass are staggering to consider. Through the lenses of our telescopes, microscopes, binoculars, and spectacles, we use glass to help us see the very big and very small (and through cameras, to document our world). Through the screens of our cell phones, televisions, and computers, we use glass to inform, entertain, and communicate. Through our fiber optic cables, we use glass to carry the Internet under the ocean and across other great distances, enabling our virtual worlds. Through orbiting satellites, we use glass mirrors to send data back and forth to Earth, and to probe the limits of faraway space. Through the windows in our homes, cars, trains, and airplanes, we use glass to modulate our sense of within and without. Through the faces of our watches, we use glass to track our sense of time. Through our various cups and vessels, we use glass to measure, mix, cook, hydrate, celebrate, and cultivate romance. Through the mirrors in our homes, we use glass to reflect on our appearance and to observe our bodies as we age. Without the technology of glass, human life on Earth would be radically different.

In solid state physics, the so-called “glass transition” is the mysterious shift that occurs when a hard and brittle non-crystalline solid gradually becomes viscous, liquid-like, and “glassy” through a sustained increase in temperature.

As this “glassy” material cools, it undergoes a process known as “vitrification” — retaining the amorphous molecular structure of a liquid while hardening into something that is effectively solid. This paradoxical quality of being both a liquid and a solid at the same time is fundamental to the enigma of glass.

It is neither-nor; it is both-and.

In this crucial twelfth ritual — equidistant from the beginning and the end of the cycle — I work with Ethan Bond-Watts to build a handmade clay cob furnace in a sloping hillside in the fields at High Acres Farm.

We intend to use our furnace to transform the ingredients we gathered and prepared in Apprenticeship into our own homemade glass — incorporating the cremated remains of my mother, and other significant materials from our land.

I use an old steel pick to break ground, beginning what will eventually be an eighteen-foot-long trench running up the hillside.

We apply the thick and stinky cob mixture to shape the walls of our future furnace.

For the crucible to hold our ingredients, we use an old clay pot which was gifted to Ethan by one of his mentors, made at nearby Goddard College in the 1970s.

Through steady work, our furnace takes shape.

The furnace has three distinct chambers: one to hold our wood and fire, one to hold our crucible, and one for annealing our glass. The doors of the latter two are made out of clay, while the heavy door of the wood chamber is made from the metal roof of the 1890s “Old Dairy Barn” at nearby Shelburne Farms, which was struck by lightning and destroyed during the time we were building our furnace.

To accelerate the airflow into the fire chamber, we insert an old High Acres Farm gas-powered “Weed Eater” leaf blower into a rusty eight-foot iron pipe — propping up one end of the pipe on a sawhorse, with the other end poking into the fire chamber of the furnace. In this way, we can protect the plastic neck of the leaf blower from melting in the powerful heat of the fire.

With all these elements assembled, our furnace is ready to test.

At dawn on November 1, 2016 (the Day of the Dead), we light our furnace with birch bark, kindling, and matches.

All day long we feed it firewood to help it gather heat.

Propelled along by the roaring force of the leaf blower.

That afternoon, we lay out our collection of powders on a twenty-foot maple slab table, made of wood that was harvested at nearby Shelburne Farms.

The ingredients have each arrived at this point through a journey of their own.

In the late afternoon, we add our ingredients.

At nightfall, we take turns sleeping in shifts on the hillside and feeding wood to the fire, as the glass transition works its magic from within the glowing furnace.

Around midnight, the fire is so hungry for oxygen that its flames are licking out of every available opening, including around the edges of the crucible chamber door, and through the small circular hole in the center of that door. These wildly flapping flames evoke a mythical Phoenix — the archetypal force of transformation, bursting forth from the crucible at the heart of the raging furnace.

Around 4:00 AM, I spot a glowing white crack in the side of the crucible, and I see the molten glass leaking away through the crack and into the furnace. The leaf blower suddenly stalls, and when I try to restart it, its cord breaks off, so that it can’t be restarted again. We assess our quickly changing situation.

Blurry-eyed and exhausted, we decide to try to make a cup before our precious molten glass is totally gone...

Ethan reaches into the crucible with his blow pipe, and gathers a layer of glass. It is thick and gummy, but still workable, and he manages to make a vessel with the glass that remains, before the crucible is totally empty.

As the first light of dawn appears in the east, we place our newly crafted vessel into a bucket of vermiculite to cool — after seven months of work, the “phase change” miraculously having succeeded.

An hour later, in the cool rising sunlight, I reach into the bucket to examine our beautiful vessel — a new sacred object, unique to our land.

We received two unexpected visitors bookending our long night of glassmaking, each with an interesting name — in the evening, a local friend named Callie (as in Kali, the Hindu goddess of creation and destruction), and the next morning, my cousin Lila (the Hindu term for the dance of reality).