Conservation of a C19th Pocket Globe
The manufacture of historic globes was well documented and both parts of this object follow a fairly standard method of production. Both are made up of layers of wood, millboard paper, plaster, printed and hand coloured paper ‘gores’ and varnish. The outer surface of the case is covered with a layer of treated leather. Both globe and case have small metal features. Historic globes suffer specific types of damage as a result of the materials that make them – each layer reacts to environmental change and aging differently resulting in the stronger materials, the wood and millboard, pulling apart the weaker plaster and paper layers.
The globe itself had survived in quite a good condition, with only surface dirt, some darkening and areas of loss due to abrasion in its varnish layer and minor corrosion of its metal elements. The case had not fared as well and had been seriously physically damaged at some point, leading to extensive historic repairs with a treated textile and cardboard. This repair was failing, meaning that the case was physically unstable. Along with this, both the plaster and paper layers were delaminating and detaching in places meaning that the object could not be handled safely.
As a paper conservator I did not have much experience in treating composite spherical objects, and was wary of undertaking any interventive treatment before I had gotten a better understanding of what I was dealing with. As it happened, an annual online course in the conservation of historic globes was being offered by the Hornemann Institute during Ireland’s first COVID lockdown, which the NMI agreed to fund. This provided me with a better understanding of the materiality of the pocket globe, its historic context and suitable treatments for the damage which had been noted. I was also lucky to be able to ask my colleagues in conservation, Hannah Power (decorative arts) and Patrick Boyle (furniture) for advice regarding materials which are usually outside of my remit. Patrick was also able to give me more information about the large repair on the container, the textile section of which matches similar repairs on harps in the NMI collection, indicating that this is a historic institutional addition and should be kept if possible.
With all this in mind, the aim of the treatment designed for the pocket globe focused on stabilizing the object for display while retaining evidence of its use life. To begin, both sections were cleaned with soft brushes and the textile and leather sections were cleaned with smoke sponges. The varnished paper was then cleaned with swabs of saliva. Remnants of polish were mechanically removed from the metal sections. The unstable section of the historic textile repair was pulled back and the acidic paper and cardboard which had been adhered to the wood and millboard below was removed and replaced with toned Japanese tissue and a wheat starch paste glue. These repairs were kept in place overnight with magnets while the adhesive dried. The damaged and fragile sections of the gesso layer were consolidated and secured with warm gelatin and loose, abraded or damaged paper was treated with a diluted methylcellulose. Finally the varnished paper was buffed slightly with a microfiber cloth.
Following treatment, the globe was stable enough for handling and display alongside ‘Celestial Spheres’, the work it had inspired. This globe was challenging and enjoyable for me to conserve as it gave me the chance to work with a type of object which I had not encountered before and to learn about the historic processes involved with its manufacture.
By Ellen Mc Keever, Paper Conservator
