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The Back to Nature project was developed as a collaborative doctoral award between the British Museum and the School of Geography and the Environment, University of Oxford. The British Museum has a large collection of limestone artefacts, some of which have deteriorated to an extent that a consolidation treatment, to improve internal cohesion, has been deemed necessary to ensure the value of the artefacts is maintained. Previous consolidation practices within the museum had centred on the use of organic consolidants. In the past, inorganic consolidants had been considered ineffective chiefly due to poor penetration depth and inconsistent deposition within the stone. Recent scientific developments within conservation, particularly the development of nano-limes, coupled with a trend towards treatments offering physical and chemical compatibility, led to the British Museum reconsidering the use of inorganic consolidants. Three inorganic consolidants: ammonium oxalate treatment, Calcite In-situ Precipitation System (CIPS), and CaLoSil have been investigated by the Back to Nature project to assess their potential for use on the British Museum’s deteriorated limestone artefacts. The investigation involved a developmental sequence of four experimental phases to assess the effectiveness of each consolidant upon freshly cut, artificially pre-weathered, and naturally weathered stone samples. In all experiments an organic silane Wacker SILRES BS OH 100 was used as a comparison. A variety of analytical methods were used including: Equotip, GrindoSonic, Scanning Electron Microscopy, Karsten Tubes, Drilling Resistance Measurement System, spectrophotometry, X-ray Diffraction and Ion Chromatography. Experiments show that the CIPS treatment could hold promise for use as a consolidant. Ammonium oxalate only appears to provide consolidation at the surface level, and CaLoSil would need modifying and more investigation before using in the museum environment. The differences noted between experiments on artificially weathered and naturally weathered stone indicate that a two-step process, involving testing on both types of samples, would give the best indication of consolidant effectiveness. High variability between samples shows a large number are needed to give an accurate interpretation of change due to consolidation.

The aim for this thesis is to motivate, critically evaluate and defend the claim that subjects are able to consciously perceive the affordances of objects. I will present my protagonist, the ‘Conscious Affordance Theorist’, with what are two main obstacles to this claim. The first of these is that affordance perception correctly understood refers only to a kind of subpersonal visual processing, and not to a kind of conscious visual experience. I claim that this results in an explanatory gap at the level of intentional action, which in order to correct we need to redefine the notion of affordance perception to include conscious as well as subpersonal affordance perception. Precisely, I claim that ‘affordance awareness’ has a crucial epistemological role to play, and that subjects must be able to consciously experience affordances in order to gain this awareness. In answer to this claim, I supplement the objection that affordance perception is defined as subpersonal perception to include the claim that any awareness subjects have of the affordances of objects they visually experience is due to them having thoughts about those affordances, and not visual experience of them. I then consider the Conscious Affordance Theorist’s response to this supplemented account. The second obstacle is the claim that conscious visual affordance perception is an impossible notion given that affordances are dispositional properties, and the dispositional properties of objects cannot be ‘seen’. In facing this objection I look to the supporting claims and motivations that lie behind it, in order to find a way for the Conscious Affordance Theorist to challenge its central claim that affordances cannot be seen. I end this thesis with an account of the Conscious Affordance Theorist’s own positive position, and a consideration of how his account has the ability to provide for conscious affordance perception in the case of non-human animals.