Seventeen Years With Jars: a Conclusion and a Small Overview About Plans

There were more than 348 natural history collections and 179 medical collections in Germany compared with 68 natural history collections in France (Charon 2014). More than half of these have parts of the collections stored in fluids, and thus they will all use jars and will all face similar problems (e.g., regularly needing new jars and effectivemethods for sealing them). After 17 years of working with jars, moving wet collections, realizing the KUR-Projekt (Neuhaus et al. 2012), and conducting many workshops, I would like to give a short overview about future ideas and plans and a brief conclusion of my point of view. In most of the wet collections I have visited or worked with, such as the ones of the Museum für Naturkunde (MfN), the majority of the jars used are glass stopper jars (e.g., the Spider wet collection at theMfN shown in Fig. 1). However, such collections also contain a wide variety of other types of glass and plastic containers with a range of closures, including glass plates, plastic snap or screw-on lids, and jars sealed with Picein, an asphaltum– rubber compound (Simmons 2014). Some closures and containers are efficient and durable for the long-term preservation of specimens, and in the past 10 years, both soda glass with twist-off lids and borosilicate glass jars have been used. Yet the question always arises related to the management of these collections: which are the best? Is it preferable to actually use borosilicate glass jars, reputed to be effective but expensive, or is it enough to consider soda–lime twist-off glass jars, which are less expensive? To answer the question, it does not seem sufficient to consider only the price and availability of these containers. Other factors are important, including the need to ensure a proper seal, consideration of the jar contents, and the need for institutions to share resources. For more than 100 years, collection assistants, curators, and collectionmanagers have been dealing with jars and have developed a large pool of knowledge and experience. While there are existing networks to share this knowledge, such as the Society for the Preservation of Natural History Collections (SPNHC) wiki (https://spnhc.biowikifarm.net/wiki) or the Natural Sciences Collections Association (NatSCA) and Global Conservation Forum lists, they are not exclusively dedicated to issues related to fluid collections. The day-to-day management of a fluid collection requires special expertise and attention to detail. The people in charge of the conservation of these collections have their own knowledge and experience to draw on, but it is difficult to find this information in books or articles. Most of the time, this knowledge is exchanged with colleagues in the museum or sometimes with well-known colleagues in the field working in other museums around the world. Beyond this small group, it is difficult at the moment to share one’s own knowledge or to write articles detailing these facts. It is only in recent years that we have come to understand what this technical knowledge represents and what we could lose if this knowledge base is not maintained. The challenges of managing fluid collections highlight the need for