Diving into Glass: Reflections on the Blaschka’s 150-year-old Glass Menagerie

by Drew Harvell, author of A Sea of Glass: Searching for the Blaschka’s Fragile Legacy in an Ocean at Risk

Becalmed in the North Atlantic on a dark May evening in 1853, Leopold Blaschka witnessed an other-worldly event. Beneath the glassy surface of the sea, a small green light appeared. Then a second. And a third. “A hundred of these suns light up at a certain distance,” Leopold wrote. “As if they wanted to lure the enchanted observer into a realm of fairies.” He describes a flotilla of bioluminescent jellyfish, drifting midway across the Atlantic. Leopold, a glassworker from Dresden, sketched the shifting colors, tentacles, and ghostly lights. Then he began to imagine the jellyfish forms as glass. Over the next forty years, Leopold and his son, Rudolf, would go on to spin almost 10,000 glass sculptures of 700 unique marine organisms that today populate universities and museums around the world.

Twenty-seven years ago, as Cornell’s new Curator of Invertebrates, I travelled to the Corning Museum of Glass to visit Cornell University’s Blaschka Collection. I entered the cavernous warehouse, filled with rows of shelves and cardboard boxes, and opened a box. Inside was a glass model of the common octopus (Figure 1). Though it was covered in dust, with a gaping hole in the thin glass mantle and a missing eye, I was captivated by the lifelike texture and posture of the sculpture. Inside another box, I found a model of a bright red, orange, and white striped sea slug. At the bottom of another was an Apolemia uvaria jellyfish. The multi-belled, fifteen-inch-high glass masterpiece depicts an animal that trails 30-foot-long tentacles in the Mediterranean (Figure 2). I uncovered hundreds of models, representing a vibrant tree of life, spanning eight phyla and nineteen classes. It was an unprecedented record of marine biodiversity from the nineteenth century.

The siphonophore, Apolonia uvaria CREDIT: Kent Loeffler photo

As a Marine Scientist, I have spent the past three decades studying ocean biodiversity and health in locations like Mexico, Hawai’i, Indonesia, Myanmar and, domestically, in the Pacific Northwest. Many of the reefs and shores that I work on are declining. For instance in 2016, rising ocean temperatures caused deadly coral bleaching and mass mortality of corals worldwide, but notably near Australia, Fiji, and Hawai’i. Bleaching occurs when symbiotic algae, relied on by corals to photosynthesize and transfer energy, abandon their hosts to starve or succumb to disease. The health of colder-water animals are also impacted. In 2013, off the West Coast of the United States, twenty different species of starfish died catastrophically from a lethal virus outbreak that continues to this day. The once-common sunflower starfish, a keystone species, is now endangered and still declining. This is just the damage that we know about. I worry about deaths of ocean critters and the possibility of unseen extinctions due to climate change, pollution and overfishing. The ocean contains many organisms that are difficult to record and monitor. In the midst of unprecedented marine mortality and ocean change, I began to realize that the Blaschka Glass Collection provided my team with a time capsule of biodiversity common in the 1860s. Were our Blaschka animals still in today’s oceans?

Six years ago, with videographer David O. Brown, I began the search for Blaschka matches around the world. In Italy, we dove at the Porto Fino Marine Preserve and located seventeen living matches. One, was the mauve stinger jellyfish speckled in purple dots. Another jellyfish, the tiny by-the-wind-sailor, relied on a raised, iridescent membrane to sail the Mediterranean. In Indonesia, we found vibrantly colored nudibranchs and tiny octopus relatives. In Hawai’i, David and I filmed by night shape-shifting octopi, watching us from coral heads and crevices, reminiscent of the first sculpture that I uncovered in the Corning Museum of Glass. Those stories of our underwater searches are now a book, A Sea of Glass, focusing on the successes and the failures of our global exploration and detailing the fragile existence of those matches still living in our oceans today.

The common octopus, Octopus vulgaris. CREDIT: Gary Hodges photo.

Early in our quest, I dangled nervously on a tether below fifty feet of pitch-black water a mile off the coast of Hawai’i Island. We had come for the bioluminescent jellyfish of the night. We watched a ribbon-like comb jelly, a kaleidoscopic Blashka match, undulating against the current. Another point of light was drifting towards me in the current. A two-lobed jellyfish trolling tentacles that might match our Praya dubia glass sculpture. It was hunting with long, gossamer strands outstretched to capture plankton, but it spooked in our lights. Giant axons in the bell fired powerful contractile muscles that zipped up the tentacles and propelled the jellyfish away. Shivering in the cold and dark, it was time for us to surface. With a final look at the waters, we began to rise with our exhaled bubbles, nervous about our conservation efforts, and regretfully leaving this latest glimpse of the ever changing ocean.

A Sea of Glass won the National Outdoor Book Award, was a top Smithsonian Art-Science Book in 2016, and honorable mention Rachel Carson Award. Fragile Legacy is an award-winning film.


Drew Harvell is Professor of Ecology and Evolutionary Biology at Cornell University and Curator of the Blaschka Marine Invertebrate Collection. Her research on the sustainability of marine ecosystems has taken her from the reefs of Mexico, Indonesia, and Hawaii to the cold waters of the Pacific Northwest. She is a Fellow of the Ecological Society of America and the Atkinson Center for a Sustainable Future, a winner of the Society of American Naturalist Jasper Loftus-Hills Award, and a lead author of the oceans chapter in the recent U.S. Climate Change Assessment. She has published over 120 articles in journals such as ScienceNature, and Ecology and is coeditor of The Ecology and Evolution of Inducible Defenses.


Curious about Undersea Robots? Sharks?

Cookiecutter Sharks ambushing a school of DolphinfishesScripps Institution of Oceanography at University of California San Diego launches its summer evening lecture series TONIGHT  with a lecture on undersea robots. Jules Jaffe, Scripps research oceanographer will speak on his “latest scheme” to use “inexpensive, miniaturized robotic floats that travel with currents, sense the environment, and report their findings back to us.” His lecture is called “Swarms of Small Autonomous Robots: A Future Vision for Ocean Observation.”

At a second lecture on July 13, Jeffrey Graham, marine biologist, will talk about sharks. “Learn how shark biologists study shark physiology, life history and behavior for insight into what allows these fishes to rank among the world’s most efficient predators.”

The lectures, which are intended for and open to the general public, take place at Birch Aquarium,  Scripps Institution of Oceanography, UC San Diego campus. See the Scripps website for more information.

The lectures are also broadcast on UCSD-TV

For further reading:

Oceans: Exploring the Hidden Depths of the Underwater World by Paul Rose and Anne Laking
Experience the California Coast book series

California Coastal Access Guide, Sixth Edition, by the California Coastal Commission
Sharks, Rays, and Chimaeras of California by David A. Ebert

Illustration of Cookiecutter Sharks ambushing a school of Dolphinfishes by Matthew D. Squillante appears in Sharks, Rays, and Chimaeras of California by David A. Ebert.