Ehrenrettung der Hermetischen Kunst (1786) — A Rare Window Into Alchemy, Hermetic Science, and Enlightenment-Era Esoterica

In the world of rare books and occult scholarship, few artifacts offer a direct connection to the intellectual and spiritual concerns of the late eighteenth century the way this 1786 German Hermetic treatise does. Printed in Erfurt by Georg Adam Keyser, this first-edition volume brings together alchemical theory, natural philosophy, early chemistry, and the evolving European fascination with secret knowledge just decades before the public emergence of organizations later associated with Hermeticism and speculative esoteric movements. Works of this type seldom survive intact, making this example an extraordinary opportunity for collectors, researchers, and institutions focused on early science and occult history.

Historical Background and Authorship

Authored by Johann Christoph Henckel and Heinrich Christoph Friedrich Knoll, Ehrenrettung der Hermetischen Kunst (translated roughly as “The Defense of the Hermetic Art”) attempts to legitimize alchemy and chrysopoeia by grounding them in observable chemical and physical principles. Rather than positioning alchemy as mystical speculation, the text argues that its methods can be demonstrated, repeated, and understood even by practitioners of “middling skill.”

This places the work squarely in a transitional era of European intellectual history. By the 1780s, Enlightenment rationalism was influencing traditional esoteric arts, prompting alchemists and hermeticists to reinterpret their disciplines through the lens of empirical science. Books like this one stand at the crossroads of magic, chemistry, metaphysics, and natural philosophy.

The volume’s German origin is also notable. Late eighteenth-century German states were major centers of Hermetic revival, Rosicrucian activity, and early Enlightenment-era societies dedicated to symbolic knowledge, philosophical inquiry, and the pursuit of universal science. Surviving works from this milieu are aggressively collected by both private enthusiasts and academic archives.

Technical Description and Physical Details

This example contains two volumes of the original three, bound together in a period leather spine with decorative paper-covered boards. Pagination includes pages 3–62 and 72, consistent with known surviving incomplete sets. Features include hand-set Fraktur type, period signatures, and foxing indicative of eighteenth-century German rag-paper stock.

The binding is original to the era and exhibits expected age-related wear including hinge cracking, discoloration, and foxing. Despite these issues, the volume remains structurally sound and highly presentable for a 238-year-old scientific–esoteric text.

Because the surviving corpus of this title is extremely small, even partially complete examples hold significant research and collectible value.

Why This Book Matters to Collectors and Scholars

Hermetic and alchemical texts from the late eighteenth century occupy a unique position in both scientific and esoteric history. They reflect the moment when mystical traditions were being reinterpreted through the developing sciences of chemistry and physics, while still retaining symbolic language inherited from centuries of European alchemical practice.

Collectors value these works for several reasons:

• Early printed alchemical texts are increasingly scarce
• German Hermetic materials are highly sought after by esoteric archives
• Eighteenth-century occult treatises rarely survive in private hands
• Works that attempt to merge science with Hermeticism appeal to interdisciplinary researchers
• First editions from regional printers such as Keyser are limited in surviving count

Very few eighteenth-century Hermetic volumes come to market in any condition, and almost none with period binding intact.

Estimated Appraised Value

Based on recent sales of comparable eighteenth-century alchemical and Hermetic works, scarcity, subject matter, condition, and authorship, the estimated fair market value for this example ranges from 2,500 to 4,000 dollars. Values may exceed this range for institutional buyers, Hermetic libraries, or advanced collectors seeking pre-1800 occult material. Because the market for esoteric and alchemical first editions remains strong and supply is shrinking, long-term appreciation is likely.

For insurance coverage, estate planning, and resale, a formal written appraisal is strongly recommended. Professional authentication and documentation significantly increase buyer confidence and protect the historical integrity of rare scientific–occult manuscripts.

The importance of authentication and appraisal

With rare occult and Hermetic books, challenges often arise in determining edition, completeness, originality of binding, and period provenance. Expert evaluation helps confirm printing date, printer identity, paper age, binding authenticity, and whether missing sections affect value. An appraisal also provides a documented baseline for insurance and offers authoritative proof of authenticity for future buyers, museums, or academic institutions.

At DJR Authentication, we examine rare books, manuscripts, alchemical texts, and esoteric works of all periods. Our evaluations include detailed documentation suitable for insurance, estate planning, resale, and more. To submit your item for online appraisal or schedule an in-person consultation, visit the services page. In-person consultations are available by appointment in Charleston, SC.