How we proceed
Firstly, the glass objects from the former territory of Schwarzburg (i.e. the holdings of the Schwarzburg residences at Sondershausen, Rudolstadt and Arnstadt) are identified and recorded. Included among these are architectural glass objects such as window panes in dwellings, princely residences and ecclesiastical buildings. At the same time, glass objects are of interest if they were produced in the area, exported from there and can now be found elsewhere.
Meanwhile, archives and literary sources are used to a) reconstruct the activities of the Schwarzburg glassworks, b) investigate the origins of the raw materials and of the agents involved in glass production (families, migration and settlement of experts), c) investigate the local, regional, translocal and transnational markets as well as intermediaries and agents and d) reconstruct the object practices in castles, churches, residential buildings or pharmacies.
What is Glass?
In the early modern period, the term “glass” was used to describe a range of lustrous materials, but in particular “ein[en] aus Sand oder Kieseln mit einem Alkali und Salz zusammen geschmelzte[n] durchsichtige[n] glänzende[n] Körper” (a transparent lustrous body fused together from sand or pebbles with alkali and salt; Krünitz, Oeconomischen Encyclopädie, 1779, vol. 18, 581).
Glass existed in different qualities and colours: “Das Glas ist, seiner Güte und dem Ansehen nach (…) von einander unterschieden. Das beste unter allen ist das Krystall= und Spiegelglas; nächst diesem folgt das weiße oder Kreiden=Glas, welches reiner, heller, durchsichtiger, und also auch besser ist, als das ordinäre Glas, welches man auch gemeines oder klares Glas, und wenn solches, [welches] in dem thüringer Walde, geschmelzet wird, eine grüne Farbe hat, grünes Glas nennet. Hierauf folgt das halbdurchsichtige Glas, und das dunkle Glas; welche beyde letztere Gattungen, wenn sie in das Schwarze fallen, schwarzes Glas heißen” (Glass is distinguished from one another by its quality and prestige (...). The best of all is crystall= and mirror glass; next to it follows the white or chalk=glass, which is purer, brighter, more transparent, and thus also better than the ordinary glass, which is also common or clear glass. If it is melted in the Thuringian Forest, it has a green colour and is called green glass. Then follows the semi-transparent glass and the dark glass; in the latter case, if it verges on the black, it is called black glass; Krünitz, Oeconomischen Encyclopädie, 1779, vol. 18, 586).
Glass was produced in so-called “glassworks” or “glass foundries” which consisted of several ovens arranged side by side and working at diverse temperatures (Fig.). These glassworks were mostly located in densely wooded areas, since they required large quantities of wood to fire the ovens and to produce the flux agent for wood ash or potash. The work in the glassworks was exhausting and dangerous due to fire, great heat and sharp glass shards. Occupational hazards frequently included cuts, burns and loss of sight.
Aims and Scopes
How extensive was the glass production? What was the use of glass in the petty state of Schwarzburg? Which areas of life did it concern? How were diverse glass objects used within the societal strata? What was the relationship between self-produced, local glass and imported glass objects? Did a European network exist back in 1600-1800 in the petty state of Schwarzburg? What is the aesthetic effect of glass ware? What is their significance as the result of material properties and what is the effect of glass in cultural memory?
From a scientific perspective, glass can today be defined in a range of ways: firstly, glass is the product of melting and solidifies without crystallization. Physical chemistry defines glass as a frozen, hypothermic liquid. Based on the material properties of glass, all substances that show a glass transition are glasses. Therefore glass has no melting point, but a so-called “softening range”. A further definition is provided by the atomic structure. Glasses are homogeneous and isotopic solids without long-range order but with order principles in the near and middle range of the atomic structure.
Generally, glass is understood as transparent, inorganic material. Industrial glass is mainly soda-lime silicate glass. It mainly consists of a mixture of sand, limestone and soda. These basic components have changed very little since the early modern period.