The Collections

The Oesper Collections represent one of the world's largest curated collections of scientific artifacts in the Apparatus Museum, books & journals in the Oesper Library, and the photos & prints collection related to the history of chemistry. These resources bring the field's rich historical heritage to life. At the same time, they reveal the importance of chemistry in society and show how this central science touches everyday life. And they demonstrate the embracing the past is essential to understanding the foundations of chemistry, as well as its present and future.

The holdings - which date from the 16th through the 21st centuries - are available to view and study at the University of Cincinnati in the Department of Chemistry. Chemists, students, historians, and the public will find a wide range of attractions within the Oesper Collections. Some visitors will be drawn by rare and ancient leather-bound books, such as "Elemens de Chymie," French for "Elements of Chemistry," which was published in 1624 - just a few years after the death of William Shakespeare. Others will be attracted by equipment including a reproduction of an 18th century retort used to separate and purify liquids, a device from around 1915 to monitor the fermentation of beer, a folding pocket camera from 1902, and an electron microscope from the 1960s. 

Aside from Jensen's personal apparatus collection, which formed the nucleus of the museum, which formed the nucleus of the museum, the vast majority of its holdings are donations from laboratories around campus and from more than two dozen U.S. colleges and universities. Most items were acquired between 1986 and 1998, when Jensen was regularly invited by various small colleges and schools to give seminars on the history of chemistry; during those trips, he often visited chemistry departments' storage areas. Other significant donations have come organically, including the M.G. Mellon Colorimeter and Spectrophotometer Collection, the O. B. Ramsay Molecular Model Collection, the Oberlin College Electrochemical Cell Collection, and the McGowan Chemistry Set Collection. In some cases, other museums, such as the Smithsonian and the Paselk Instrument Collection, have donated duplicate items from their holdings.

In 2008, the museum's displays were first posted online, and this is now the most important stimulus for donations. Thus in 2010, a donor in Colorado who had visited the website offered the museum a 1950s-era Craig countercurrent distribution train, which was used for extraction and purification in biochemistry. A description of this instrument on the museum's website inspired, in turn, a donor in California to give an even earlier cylindrical version of Craig's apparatus in 2014. All of this means that, despite an ample endowment, very few of the museum's acquisitions have been purchased from antique dealers. In 2023, the museum's online displays were migrated to a JSTOR collection where the artifact photo collection can currently be viewed.

Aside from being relevant to chemistry, the only restriction on adding to the collections is "The Sherman Tank Rule." This refers to the massive vacuum-tube-based instruments that became common in chemistry after World War II. During that time, there was a rise of commercial mass spectrometry, nuclear magnetic resonance spectrometry, and electron spin resonance spectrometry. Through various instruments from this period have been offered, both their bulk and weight have precluded adding them to the collections. In short, if an item is too big to fit in a display case, it is generally turned down. However, recent exceptions include a Siemens Elmiskop IA electron microscope from the mid-1960s and a Varian E-4 electron paramagnetic resonance spectrometer from the early 1970s. The university libraries made space for the instruments' display in the Chemistry-Biology Library.

In contrast to the apparatus collection, virtually all additions to the book and journal collection have been purchased from used book dealers throughout the world using Oesper Endowment funds. Through English, German, or French are preferred, items in other languages, such as Chinese, Japanese, and Latin, are in the collection. While the collections contain many secondary studies of alchemy and a few primary documents, the official collection policy favors the purchase of non-alchemical works.