Metabolic Matterings

A digital and so-called “sensory” facsimile lives in a subterranean museum complex in Montignac, France, adjacent to the cave it simulates (and to a prior replica, forged by a single painter and two sculptors, without additive technologies).1 Rendered from the first complete 3D scan of Lascaux Cave—mothership-like, even figurative, in contour—Lascaux IV’s form was milled by CNC machinery from polystyrene, mineralized with a “stone veil” coating of stone powder and acrylic resin, and then painted by analog hand, using commensurate instruments and techniques of “paleogesticulation” by a team of artisans in Montignac’s Atelier des fac-similés du Périgord (AFSP). Vetted by a scientific committee for 1:1 millimeter exactitude, this synthetic material fiction and the aura it exudes is so convincing, so granularly wrought, that certain visitors believe themselves to be inside Lascaux Cave itself.

Soft architectural phenomena imbue Lascaux IV’s subtle artifice with organic tonality: visitors enter through a condition chamber of sorts, and echoing descent, the facsimile’s dim body sustains a bite of chill. Its acoustic schema was designed and integrated by Daniel Commins, a renowned concert hall and opera house acoustician, whose acoustic map of Lascaux Cave permitted analysis of its Paleolithic soundscape equivalent, which he retrofit for the facsimile. Yet because Lascaux IV hasn’t suffered algal overgrowth, dampening to sound, Commins’s acoustic transposition allows us to “hear through” roughly 25,000-year-old sound: we can hear what is no longer available to be percepted with any clarity in Lascaux itself. It is this sonic environment and its symphony-hall-like acoustics—finely tuned for oral transmission in the “mid-speech” register—that is currently thought to have been an instigating force behind the paintings for which Lascaux Cave is known.2 Such timescaling affordances are not mirrored across all sensory modalities, however, in that the facsimile emits no odor. No tinge of mineral pheromone, oily secretion, or vaporous precipitation of microclimate. And hence it lacks the atmospheric thickness and proprioceptive tactility that odor—as sound—would endow its cavity with.

This omission led to the development of an iterative scent edition: an environmental eau de parfum, titled Exuviae (2022), that I evolved with nose Barnabé Fillion.3 Atomized in fine mists as a “scent climate” alongside earamphore (2022), a multichannel sound installation co-created with vocalist Jessika Kenney, both works were vibrotactile and amphibious in their effect, introducing virtual weathers into space. A sensory prosthesis and liquid “scaffold,” I hoped that the scent’s frequencies, transmitted via volatiles, would induce percipients to notionally “remote sense” across millennial faultlines, as Lascaux IV affords through sonority. That its effect, upon diffusion, would produce spatiotemporal slippage and act through the limbic system, circumventing synapses, just as odor molecules and taste buds do—inducing precognitive kinds of “knowing” in that interstice between (raw) sensation and (processed) perception.

Unsuccessful in procuring the supercritical CO2 extractor technology that is used in the fragrance industry to produce (purportedly) “nature-identical” absolutes in minutes, Fillion and I resorted to premodern methods of maceration to evolve our scent blend, in principle akin to making skin-contact wine. Geographically promiscuous, I gathered sample “earths” from multiple cave environments and disused mines, including cave dirts and cave waters, mica flakes, cicada nymph skins (surface molts of seventeen-year subterranean gestation), microbial moonmilk deposits, and oyster mushroom fruiting body.4 (Paleoanthropologist Paul Pettitt, who suspected his colleague Alistair Pike “may have some stalactite spare,” advised against samples from caves with “large levels of bat hibernation” to avoid bat guano’s vinegar scent profile.)

In contrast to machine-led methods of extraction, an ecopoetics of touch by skin-contact plays out in liquids in maceration. Maceration, which means “to make soft,” “extracts” by infusing a carrier medium with odor compounds from a sample substance, generating a supposed index of essence. As solutions start to take on olfactive personae, a kind of cooking (sans chef) by self-reassembly—of “agentized chemistry”—takes place in nano registers.5 Nearer to alchemy than science, maceration converts solid-state matter into volatile minglings of molecules.

Emma McCormick Goodhart, Moonmilk depositional biomatrix from Mount Pilatus, Switzerland, sampled by Kathrin Füglister and Moritz Lehner, with Barnabé Fillion at Arpa, Paris.

To pay attention to the messages of macerations themselves as they emerge—to sound liquid matter sotto voce—is to practice listening. The Japanese have a word for this, “kodo,” around which ceremonies are built that engender sociality through scent notes. Moonmilk’s richly complex and ozonic notes are deeply geological. Their aura of dark, recessive spatiality and drenched plaster reads like a microhistory of built environments and subsurface construction, haunted by unanticipated, nearly spectral musk: an animalic layer. To this base, we added mitti attar—a wet clay distillate from Kannauj, India, that is heavy in geosmin, the cyanobacteria- and Streptomyces-produced compound responsible for petrichor (to which humans are exceptionally tuned to detect, likely in deep-time evolution in order to locate water)6—as well as aldehyde, in high-frequency, tongue-on-battery, metallic timbre. “Climatized” in space, Exuviae’s profoundly saturating effect of permeated microclimate, with an undertone of dust, conjures a sense of the “fabric” of minerality, of porous cavity, aperture, and the stone that enframes it. It opens up a riddle that accompanies ancestral venture into subterranean space, more haptic than optic: what prompts the impulse to inscribe surface media, especially in unlit environments? What soft forces echolocate us to sedimentary canvases? 

Ichnofabric fossil made by Dimorphichnus quadrifidus. Photo: Gennadi Baranov, 2018. Source: Fossilid.info.

Underground, tissue-like geotactility among mineral interfaces invites contact. We know this from residual marks left behind, sometimes sited, improbably, in hard-to-access places of great resonance within cave systems. (By reproducing acoustic phenomena, archaeoacoustical findings evidence that marks and sonicity are often correlate.) Readymade host environments, mineral thresholds in such sensorial cocoons are matrices susceptible to mark, whether tooled or unaugmented, that become media once tattooed. Terminologies in geology and paleoecology exude textile-register softness, too: “ichnofabric” connotes the sedimentary layer that microorganisms bioperturb or bore through, leaving a mille-feuille of trace fossils of varying intensities.7 Soft-bodied animals, like slugs, whose silken trails are incidentally glyphic, pioneered what it means to line-make (i.e., draw). An aggregate of tissues, the world, Michel Serres writes, “is a mass of laundry.”8

R. Robert, Flutings in Grottes de Gargas, France, in Jean Clottes, World Rock Art (Los Angeles: Getty Trust Publications, 2002).

In the hominid register, a visually kin genre of gestural “channels” drawn directly into soft surface strata are known as finger flutings, which were often, as in the caves of Rouffignac and Gargas, made by infants with piercing degrees of syncopated intentionality.9 Fluted into clay-like sediment, these choreographic notations are not dry, but putty in abiotic substrate, resisting resolution and vulnerable to erasure. They remain in situ, in part adhered via the still-moist pliability of mineral scaffolds that host and mutually ecologize them. Artificial marks in organic matrices, as biomorphic as insectoid tunnels or bear-claw tracks, their animacy catapults forward and back in time and across specieal boundaries: not as a pastiche of prehistory, as in “Teddy Bear Patriarchy” iconographies of bison, spear and hunt, but as an iconoclastic index of deep-time inclination.10 Art, framed as an impulse to imprint into some threshold, is “born like a foal that can walk straight away.”11 Trace fossils may have been among the emergent practice’s first visuotactile referents.

Infant-made flutings were frequently made into moonmilk, a chalky biogeochemical secretion and speleothem deposit—part abiotic calcium carbonate, part microorganismal—that accretes in caves around the world and acts as a microbiome. Akin to lion’s mane, young ricotta, or wet concrete in texture, moonmilk was first named “lac lunae” by Conrad Gessner in 1565 for its optical likeness to the lunar surface, and then thought to be a fungus or rock. Gessner’s analogy may have far-reaching application, for a recent study by University of Malaga’s Laser Lab suggests that moonmilk could prove crucial in helping identify biosignatures in Martian caves on future astrobiological missions.12

Illustration of “lac launae” in Ortus sanitatis. De herbis et plantis (1517). Source: New York Academy of Medicine.

On Earth, moonmilks have been harvested and “mined” from caves (in Switzerland, Jerusalem, Malta, Tibet, and elsewhere), traded widely, ingested for pharmacological reasons (to alkalize the stomach, increase milk supply, tend the complexion), and spawned whole categories of false “milk” simulacra for millennia. Lore holds that performative rituals occasionally accompanied these treatment regimes; shouting an ailing person’s name where moonmilk had been mined was thought to speed their cure.13 In contemporary ricochet, efforts to isolate lunaemycin in moonmilks, and to synthetically cultivate it for potential pharmaceutical applications, are underway at the University of Liège.14 Did infants in Gargas intuitively lick their digits after they signed off? Or were parents, still suckling their young, coaxed by its lactational look?

What accounts for how earth exerts its invitational lure, sometimes addictively, inducing consumption of materials that enclose our lived environments’ architectures and earthenware? The “gustohaptic” drive to ingest earths is, perhaps, commensurate with an urge to inscribe; each unfold as a kind of contact, touch, and geospatial rite of metabolic conversion. Taste and touch are also their anticipation. Pathologized by Western medicine, cravings for “non-nutritive” earth(s) (often clays) are transcultural and ritualized, whether alimentary, curative, or symbolic, to the extent that they exceed the logics of mineral deficit explanations and point towards larger ancestro-metabolic flows of matter through microbiome across the planetary register. Earths are sampled and remixed, as if starter cultures, cycling sideways from earthenware into earthenwear—especially when ingestion takes place simultaneous to pottery-making, or where “a lady … daily enjoyed the clay figure of a statue for years.”15

Instances of this in ethnographic studies, many compiled in 1930 by Berthold Laufer, curator of the Department of Anthropology at the Field Museum of Natural History, Chicago, are immense in variety and preparation.16 There is a whole alimentary cartography, rich in mouthfeel, in these studies: earth rice, stone meal, and mineral flour (“shi fen”) to mitigate food scarcity in sixteenth-century China; a recipe for steamed white clay flour (“kwan-yin”) and glutinous rice balls (“chaoqi”), supposed to remind travelers of their village of origin, that dates back some 4,000 years; cakes rendered from “pulverized rice dipped in floating mud” in Luoyang, China, during a famine in 618 CE; a “kneaded earth and charmed water” cure distributed by “Mud-pill Ch’en”; a soup distilled from clay and lily roots in Tsietonai (“eat-earth-valley”) in Aino, Japan; “ampo” clay in Java, formed into cakes covered in salt, coconut oil, and roasted; an “aluminous earth” gathered in caves and shaped into hard balls in New Caledonia in the South Pacific; “earth fat” (“nute-echen”) mixed with reindeer milk in Kamchatka, Russia; yellow earth, called stone butter, in Siberia to treat cholera; sweet-tasting termite dirt, chewed like biscuits, in Zimbabwe; factory workers spreading stone butter talc on their lunch sandwiches at the Meisen porcelain pit, and at Kyffhäuser sandstone quarry in Germany; mountain butter in Switzerland; pottery sherds eaten by women in Patna, India, and in Peru, after consuming water from those vessels; and seventeenth-century Mexican búcaro ceramics, made from fragrant red clay, are both served from and ingested: the Infanta Margarita Teresa is presented with such a vessel in Diego Velázquez’s Las Meninas (1656).

A microscopic view of Kaolinite. Image by Michal Skiba, Institute of Geological Sciences, Jagiellonian University, Kraków.

More broadly, geophagic offshoots might count metallurgical techniques among miners of “tasting” ores while prospecting, documented in sixteenth-century Europe, when metals were believed by some to be “congealed juices of the earth.”17 To determine resource-rich sites, miners would variously sample earths directly on the tongue, in a vessel of rainwater to sip and assess flavor, or crack fragments between their teeth. Audition and olfaction, too, could differentiate mineral presences: some minerals emit odor when pounded with iron.18 Smell and taste, understood as techne, perform as analog detection technologies; modes of sounding—or hearing through—matter that help prearchitect those excavatory circuits responsible for feeding raw material to the as yet unbuilt environment. Flavor sensation is navigational clay to cognition.

Such haptic practices of earth-eating and earth-tasting—both genres of earth-sounding—make inadvertent contact with deeper-time physicochemical processes. Graham Cairns-Smith’s clay-life hypothesis proposes that clay minerals, for their sticky pliability and capacity to self-assemble and mutate, to synthesize and degrade, served as the prebiotic scaffold from which organic life first emerged some four billion years ago.19 Notionally “nonliving” and “inorganic,” minerals, in this conception, were actually the planet’s first catalyst lifeforms, and help puncture dichotomies of organic and inorganic, biotic and abiotic, that still operate and obscure continuums where clays are agents instead of animation. That clays, more recently, were returned from Mars by NASA’s Curiosity rover further “sediment” the material as an index of past life and possible habitability. Soft futures are also soft pasts, and flavorful at that. To lick clay, to taste metal, or to eat earth is to condition the very possibility of habitat creation.