This is a guest blog post from Hillary Kativa, Chief Curator of Audiovisual & Digital Collections at the Othmer Library of Chemical History at the Science History Institute.

 “So, what do you have, pictures of chemical formulas or something?” Such is the common refrain when I introduce myself as the Chief Curator of Audiovisual and Digital Collections at the Science History Institute (formerly Chemical Heritage Foundation) in Philadelphia. The quick answer to this question is yes, we have some pictures of chemical formulas, but we also have so much more, a cornucopia of rare and modern books, manuscripts, photographs, advertisements, scientific instruments, glassware, and fine art reflecting the history of science from the Roman Empire through the 21st century. As I like to say, we collect a little bit of everything and we’re thrilled to now share those materials (6,056 and counting!) in the Digital Public Library of America through PA Digital.

Launched in February 2018, our Digital Collections site is a curated selection of items showcasing the particular strengths of our diverse collecting areas, including alchemy, scientific instruments, and health and medicine. We also select materials for digitization with an eye towards what’s unique, interesting, and different, often asking ourselves “Are we the only ones that have this?” or “Would people be surprised to know we have this?” With that criteria in mind, here’s a look at some of the hidden gems you’ll discover in our Digital Collections.

Phil Allegretti Pesticide Collection

Pesticide cans, sprayers, and diffusers, oh my! Collected over several decades by Phil Allegretti, an exterminator and weed-control specialist, this collection of 3-D objects and ephemera is a lens into a time when DDT was hailed as a “miracle pesticide” and aerosol spray cans were common household objects.

Cenol Moth-Proof.
Just press the button... Bugs Drop Dead!
FlyDed Insect Spray.

Witco Stamp Collection

Spanning the years 1910-1983, this collection of international postage stamps and philatelic material offers a unique view into how scientific achievements have been celebrated and commemorated and boasts portraits of many notable scientists, including Marie Curie, Albert Einstein, Louis Pasteur, and George Washington Carver.

First Day Cover commemorating George Washington Carver, 1948.
Postage stamp on souvenir sheet from the Ivory Coast commemorating Max Planck's Nobel Prize in Physics, 1978.
First Day Cover commemorating "A Century of Modern Chemistry", 1976.
Postage stamp from Togo commemorating the 100th birthday of Albert Einstein, 1979.

Dye Sample Books

The history of dyes and dyeing is a core strength of our collection and we’ve got a diverse range of sample books featuring feathers, yarn, and food coloring to prove it.

Dyed feathers, Ausfärbungen auf Federn.
Benzo Colours on Cotton Yarn, Part I, 1921.
National Certified Food Primary Colors, National Certified Food Colors, 1930.

Roy G. Neville Historical Chemical Library

Collected by Roy G. Neville (1926-2007) between approximately 1950 and 2004, this collection includes many landmark titles in the history of science and technology, such as a first-edition of Robert Hooke’s Micrographia and Michael Maier’s famed alchemical emblem book Atalanta Fugiens. The collection is also especially strong in a range of topics, including chemistry, mining and metallurgy, dyeing and bleaching, gunpowder and fireworks, and pharmaceutical chemistry.

Emblema I. Portavit eum ventus in ventre suo, 1618.
Alchemical laboratory, 1652.
Emblema XXIX. Ut Salamandra vivit igne sic lapis, 1618.

Underwood & Underwood Stereographs of Manufacturing Industries

Often used for teaching, stereographs were a kind a proto-Power Point popular in the Victorian era, creating an immersive, 3-D effect when viewed through an optical device known as a stereoscope. This collection, which came to us from the Chemistry Department at Oberlin College, depicts various stages in the industrial manufacture of glass, steel, iron, and salt.

A reservoir after evaporation – turning up the salt – salt fields, Solinen, Russia, after 1895.
Splitting cylinders on splitting bucks ready to flatten, after 1895.
Blowing pipettes for laboratory use, in a glass factory, after 1895.

Edward G. Mazurs Collection of Periodic Systems Images

Of course, no history of science collection is complete without some periodic tables, but the Mazurs collection notably focuses on alternative layouts and designs, including circular, cylindrical, pyramidal, spiral, and triangular forms ranging in date from the 1860s to the 1950s. This is truly the periodic table as you’ve never seen it before!

Periodic table in the style of spiral with varying sizes of revolutions, designed 1926.
Periodic table in style of helix wound on one cylinder with interrupted short and medium periods, designed 1949.
Symmetrical series table constructed as a triangle, 1937.

These highlights are just the tip of the iceberg and we hope you’ll visit to explore and discover the true breadth of our Digital Collections. And underscoring our commitment to make our collections accessible, all of the images in our Digital Collections are freely available for download in a variety of sizes and formats, including TIFF, JPEG, and PDF. We’ve also applied standardized rights statements to provide clarity on copyright and facilitate reuse so there’s nothing stopping you from finding the perfect alchemical illustration for your next holiday card or whatever else your imagination dreams up. Happy searching!

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