The iconic discovery in 1912 of X-ray diffraction by crystals has revolutionized physics, chemistry, biology, and ultimately also life sciences, by providing a powerful method for structural characterization of drugs and drug targets used in molecular medicine. The first X-ray diffraction was recorded by an assistant (Walter Friedrich) and PhD student (Paul Knipping) under the instruction of a theoretician Max (later von) Laue, who two years later was the sole recipient of a Nobel Prize (with the award ceremony in 1920) awarded for this discovery. The experimental setup, now on display in Deutsches Museum München, is labeled “the original Laue apparatus”, which is doubly incorrect: Laue himself never experimented with it, and it has a number of reconstructed parts due to loss, or even theft in the Museum itself. Also, the “first X-ray diffraction photograph” is enshrouded in a mist of ambiguity. Laue’s Nobel medal was deliberately dissolved in aqua regia to evade identification and confiscation by the Nazis. A replica was minted but it has been lost without a trace. The distorted (embellished) account of this fundamental discovery makes one wonder: is it acceptable to repeat narrations about scientific achievements with some departure from the historical truth? We answer “reluctantly yes”, with the caveat that all possible effort should be expended to rectify the picture. And this article is trying to achieve exactly this, with respect to one discovery in physics.

The purpose of the paper is to discuss the Zernecke family’s library curated by PAN Biblioteka Gdańska.
Walter Friedrich Heinrich Zernecke (1862–1925) bequeathed his book-collection (1321 volumes) and his family collection of souvenirs to the library. The author reconstructed the contents of the collection on the basis of marks of ownership that occur in the survived books. The collection consists mainly of books devoted to historical, heraldic and genealogical studies (by Jacob Heinrich, Daniel Andreas, Valentin Heinrich, Wilhelm Ferdinand and Walter Friedrich Heinrich). Zernecke’s manuscript collection contains materials written by prominent members of the Zernecke family (Jacob Heinrich, Heinrich and Daniel Andreas). The most valuable part of the collection is a group of iconographic materials including an oil painting (Heinrich Zernecke’s portait by J. Wessel), engravings and photographic portraits of the family members and their book plates.