After Ehrenberg

Hand drawn and watercolored images of Volvox microscopic algae from the Ehrenberg historical collection

Water colored illustrations of Volvox, fresh water algae from the Ehrenberg Collection

When I was early in my art and microscopy journey I was diligently studying and identifying the amazing microorganisms I was seeing. Excited by the world I was uncovering, I ate up identifications, discovering wonderful Latin species like Navicula and Pinnularia. In my research, the same name kept coming up: Ehrenberg. Diatoms, desmids, protozoa, and other organisms often bore the designation after Ehrenberg.

Why was the name Ehrenberg attached to so many organisms and taxonomy? Christian Gottfried Ehrenberg was one of the most prolific scientists of his time. His foundational work studying water, soil, and rock samples from around the world. His focus on microorganisms led to tremendous advances in our understanding of microscopic species, including describing a tremendous variety of species.

While researching Dr. Ehrenberg, I stumbled upon the Ehrenberg Collection which is available online for download and research. Exploring the collection, I was entranced by the thousands of scientific illustrations. Sometimes depicting tiny fragments or whole assemblages, Dr. Ehrenberg’s artistic accomplishment was incredibly inspiring. More than that, the illustrations were grouped by place, showing Dr. Ehrenberg’s ideas about microorganisms and geographic location matched my ideas.

I reached out to Dr. Lazarus, the now-retired collection curator, for permission to use the illustrations in an artistic context. Dr. Lazarus was generous with his time and knowledge, and my project idea was formed.

Sampling After Ehrenberg

I have always been inspired by microorganisms defining a sense of place. A place’s microbiome is its fingerprint, a critical infinitesimal infrastructure upon which macro life lays its groundwork. Microbes define a place.

The After Ehrenberg project attempts to re-trace the sampling locations Dr. Ehrenberg used to reference while creating his master catalog. Using the database reference materials and illustrations, I am sampling at locations 150 years or more after the original specimens were taken, trying to be as faithful as possible to the original materials and places. I then take those samples, observe them under the microscope, compare them to the historic illustrations, and create an illustration of my own displaying the microorganisms I observed.

Hand drawn pencil sketeches of various diatoms from the Ehrenberg collection

Illustration of microorganisms found in samples taken from Oregon, United States from the Ehrenberg collection.

Reflecting the Changing Western Landscape

My project focuses on locations west of the Mississippi River in modern-day Washington, Oregon, Idaho, Utah, Nevada, and California. This part of the collection is attractive to me due to my proximity; I can drive to and explore often obscure locations from my home in the Pacific Northwest.

The Mountain West also represents a very specific and small part of the collection. These samples were mostly collected between 1825–1875, during an era when most of what is now the western United States was yet to be colonized extensively. California was in Spanish control, Washington was a part of the larger Oregon territory, and much of the nation awaited the brutal results of manifest destiny. The database refers to Oklahoma as Cherokee Territory, a very telling label for a historical marker.

Most importantly, the West represents land that experienced tremendous changes in 150 years. Many of the sample locations in the United States were on or near large cities like Cincinnati or Philadelphia, well-established and urban areas in the 1850s. The West had yet to see the extensive dam and reservoir system, fully experience the gold rush, or transform former deserts into rice, almonds, apples, and cherries to feed the world. With major natural and ecological changes, what changes had the microbiome experienced?

Hand drawn pencil sketch of diatoms and other organisms from the Great Salt Lake, Utah from the Ehrenberg collection

Diatoms and other organisms from The Great Salt Lake, Utah

Location Research

Clara Ehrenberg, Dr. Ehrenberg’s daughter, was responsible for cataloging and organizing the collection. I referenced her hand-written and scanned in the catalog as well as a machine-readable .csv file that matched micas (microscope slide covers were originally made from thin sheets of mica) to samples.

Using this information was not always easy. The place names are written in Victorian German, using non-standard spelling. The scanned script is not easy to read in places as well. Collection reference databases were not always complete or correct either, often referencing missing samples or with transposed information. I gave myself a challenge interpreting place names rendered in antiquated German, a language I do not speak.

Scanned handwritten text of location names in Victorian German handwriting

Example of hand-written sample reference log created by Clara Ehrenberg.
Note the unreadable modern notation on the paper and the reference data.

Many of the samples came from famous expeditions and people. Using the above reference as an example, some samples are labeled with “Whitney,” referencing Josiah Whitney, leader of the California Geological Survey. Most of the Whitney samples are likely from his survey work before 1868. Not surprisingly, many of the California samples correspond to gold rush era locations of interest.

Using historical name places, survey maps, and lots of educated guesses, I mapped out sample locations. Some locations may never be known due to a lack of data, incorrect recording, or lack of correspondence. Additionally, some places simply no longer exist.

Ultimately, I tried to be as faithful as possible to historic sample locations while using publicly accessible water and soil access. Although challenging, searching out these places has led me to locations of incredible beauty and interest I would not visit on my own.

Long map of the Oregon Trail with the trail outlined in red

Map of Oregon Trail. I used this map as a reference for where expeditions may have camped and collected samples. Map courtesy of The Library of Congress.

Collecting and Observing the Samples

After visiting the historic sample locations, I collected samples of water and soil, mostly river or lake sediment. I photographed each location, labeled the sample, and noted the day and time of collection

I would then observe the samples under the microscope and compare them to the images Dr. Ehrenberg produced, identifying and contrasting the organisms I observed. I extensively document the sample contents via a digital microscope camera.

Recording a sample collected from the Columbia River at the Deschutes River. This location was a popular crossing for the Oregon Trail and a likely sample location from one of the Frémont expeditions.

Dr. Ehrenberg’s Illustrations as Inspiration

Using the live sample and reference images and videos as well as Dr. Ehrenberg’s illustrations, I created the final watercolor illustrations. Dr. Ehrenberg himself occasionally added watercolor to his illustrations. Using those materials helps honor his work. I also use algae pigments extracted from microalgae like spirulina to paint my pieces and charcoal collected from local wildfires to further add a sense of place to my work.

Dr. Ehrenberg produced assemblage illustrations as part of his work, large pieces or roundels that combined many types of organisms together to illustrate the microbiome of a location or sample. Many of these illustrations are included in his master work Microgeologie and likely served as a size reference, using the circle as his microscope field for scale. I am using his compositions as inspiration for my own pieces.

Dense pen illustration of 11 round compositions with diatoms overlapping in them. One square has been cut from the paper.

Roundels for various microorganisms grouped by place, including Oregon in the upper left corner. One illustration seems to be cut from this page.

The Columbia River at the Deschutes River, ink, algae pigment, watercolor, forest fire charcoal on paper

About the Ehrenberg Collection

The Ehrenberg Collection provides an open, publicly downloadable database that contains all of the drawings from the collection as well as catalogs detailing more about the sample sources. Dr. Ehrenberg’s daughter Clara worked diligently to catalog and order the huge collection, allowing for easier future study.

The video below highlights Dr. Ehrenberg’s tremendous scientific and artistic accomplishments, including some of his amazing scientific art.

Ehrenberg collection overview courtesy of Journey to the Microcosmos

View and download the public Ehrenberg Collection database

View and download Dr. Ehrenberg’s books on Archive.org

All Ehrenberg Collection images are used courtesy of The Museum of Natural History, Berlin. Thank you to Dr. Lazarus and the staff of The Museum of Natural History Berlin for their support of this project.