Session Chair: Giorgio Strano (Museo Galileo, Italy)
Preservation actions on instruments for electrical measurements by means of in situ physico-chemical investigations
Author: Emma Angelini
Co-Author: Margherita Bongiovanni
A preservation campaign is going on in Politecnico di Torino on the important collection of instruments and equipments for electrical measurements coming from the Department of Physic, and from the laboratory for the Superior School of Electronics, founded by Galileo Ferraris in 1888, and ceded to the National Electronic Institute Galileo Ferraris when settling it in 1934. The collection includes a wide range of instruments employed for didactic purposes and research from 1920 to 1960: electrometers, voltmeters, amperometers, galvanometers, valve and battery testers, power supplies, converters, electrical analysers, etc.
These multimateric artefacts are in different conditions of conservation and the definition of tailored conservation strategies cannot ignore the knowledge of the chemical composition of the constituent materials as well as the one of the superficial layers, for example varnish, lacquers, corrosion products, etc..
The preservation campaign is carried out by means of in situ non invasive analytical techniques, X-ray fluorescence (XRF) spectroscopy and Raman spectroscopy, performing the measurements with portable instruments, as well as electrochemical characterizations by means of electrochemical impedance spectroscopy (EIS), to assess the protective effectiveness of the corrosion patinas or of the coatings on the artefacts.
Different corrosion morphologies related to the different metallic materials and to the different exposure conditions to the environment have been found among the instruments of the collection, rather common phenomena of galvanic corrosion resulting from the coupling between alloys of different nobility, as copper-based and iron-based alloys or gilded elements. have also been observed. Three case studies will be described in detail.
Management of Polychlorinated Biphenyls in Ingenium’s Scientific and Technological Collections
Author: Skye Marshall
Co-Author: Erin Secord
Polychlorinated biphenyls (PCBs) are a highly regulated class of organic compounds with negative toxic effects on human health and the environment. PCBs can be found in a variety of scientific, technological and industrial objects including computers, X-ray units, microscopes, sensors, and other electronics. Despite their prevalence in collections containing modern manufactured objects, PCBs in heritage institutions is only recently understood. To contribute to the field of knowledge related to PCBs in collection objects, Conservators at Ingenium - Canada’s Museums of Science and Innovation developed a risk management approach to the identification and remediation of of artifacts that may contain PCBs, This process was implemented during an ongoing large-scale collections move to a new purpose-built facility, resulting in over 1500 objects identified as containing PCBs or possibly containing PCBs.
The Ingenium PCB approach was holistic and innovative. PCB risks were managed with consideration of Regulators’ requirements, collection value, health and safety, and resource availability. This presentation will discuss Ingenium’s PCB management practices and the next steps in increasing awareness of PCBs in the Heritage sector.
All Charged Up and Nowhere to Go: Preservation Issues for Batteries in Collections
Author: Erin Secord
Batteries are common in technological and modern collections and present a number of health and safety and preservation risks that should be well understood and managed. Many historic objects contain, lead-acid nickel-cadmium, and alkaline batteries, while Lithium-Ion batteries may be found in objects manufactured after 1991.
Batteries are a form of stored energy, usually involving metals and electrolytes that can cause harm to human health, the environment, and collection objects. Ingenium has identified, preserved and managed over 400 battery objects and is undertaking collaborative research into the safe long-term storage of Lithium-Ion batteries.
This presentation will outline the preservation issues related to batteries in collections, Conservation treatment case studies for lead-acid and alkaline batteries, recent Lithium-Ion Battery Safety research undertaken by Ingenium’s Senior Research Fellow, and our next steps in understanding and preserving batteries in Museum collections.
Study and restoration of two microscopes from Geneva's Museum of the History of Science
Author: Mathilde Sneiders
The study and restoration of two microscopes from Geneva's Museum of the History of Science has revealed recurrent and visible alteration to scientific instruments.
The first microscope with its wooden case probably dates from the end of the 18th century. Residues of old white cleaning products are visible on the brass parts and in the interstices, some wooden parts are broken.
The second microscope, by Pillischer, dates from the 19th century. The varnished brass is corroded.
The CleanLaB project developed at the HE-Arc in Neuchâtel, proposes to treat varnished brass using active agents such as traditional complexing agents or greener alternatives (for the user or the environment) to stabilize degradation and reduce the corroded appearance under the varnish.
Tests and treatments were carried out using gels and playing with different parameters (pH, application time, type of active agent, viscosity, etc.). The aim was to obtain a satisfactory and uniform appearance for the varnished brass using the cleaning methods and products recommended following studies carried out in recent years by Julie Schröter and the HE-Arc of Neuchâtel.
