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Paper bookbindings have been disregarded for centuries by scholars since they were only considered temporary covering materials for manuscripts and books. Recently, there is a willingness to reconsider these bindings and to evaluate their role. Thanks to the collaboration with the Marciana National Library in Venice, which stores an impressive collection of 849 detached bindings, the current research provides a chemical-physical elucidation about the composition and the manufacture of paper bookbindings realized between the 16th and the eighteenth century in the Venetian area. A selection of bookbindings was analysed by the means of complementary methods (thickness measurements, Attenuated Total Reflection—Fourier-Transform Infrared Spectroscopy (ATR-FTIR), Pyrolysis–Gas Chromatography–Mass Spectrometry (Py-GC–MS) and X-Ray Fluorescence (XRF)). Data evidence the presence of cellulose as the main component of paper pulp; hemicellulose and lignin were identified too, probably related to the presence of linen/hemp rags in the paper production. Gelatine was detected muck likely related to paper sizing; among inorganic additives CaCO3 was found in all samples. The presence of waxy material may be due to past undocumented conservation treatments. [ABSTRACT FROM AUTHOR]

This paper presents the study of the indoor climate of the Scuola Grande di San Rocco in Venice: it is a 16th-century emblematic example of a historical building. The renowned Tintoretto large paintings magnificently decorate the Scuola. The monitoring and control of microclimatic parameters such as Temperature (T) and Relative Humidity (RH) are pivotal to establish proper conservation policies in museums' environments. Fragile artworks had been preserved for centuries in "natural climate" conditions, in the framework of historical buildings. In such ambiances, T and RH followed outdoor variations yet mitigated by the hygrothermal inertia of the building. Available indoor climate monitoring protocols consider T and/or RH values, but they do not allow a straightforward comparison of relative fluctuation of T and RH values through time. This paper presents a flexible methodology to visualize T and RH variations. The protocol considers the calculation of time-related index to understand the magnitude of daily (DF) or weekly fluctuations (WF), and the speed of the weekly fluctuations (SWF). The presented method introduces the calculation of climatic excursions index (ICE). The ICE is innovative because it allows us to compare the microclimate of different buildings, and it will enable us to quantify the time in which T and/or RH fluctuate outside reference ranges, even in the case that detailed information on materials and construction methods is lacking. Indoor microclimate variations have been compared with the outdoor ones: this helps to define the hygrothermal inertia of the building. • Many artworks preserved in historical buildings show a good state of conservation. • Art collections survived during centuries with no conditioned climate. • Fixed ranges for T and RH are not always applicable for historical buildings. • Indices of T and RH are more adapted to characterize the actual indoor climate. • Hygrothermal inertia in historical building enable sustainable conservation. [ABSTRACT FROM AUTHOR]

Architectural limestone surfaces are particularly susceptible to decay from natural and anthropogenic acidifying gases and particulates. This investigation evaluates environmental conditions, air quality, and decay patters on Istria stone surfaces of four palaces in Venice (Italy): Ca' Bembo, Ca' Bottacin, Ca' Foscari, Ca' Dolfin. Climate parameters and air quality indicators are used to discuss the atmospheric influence on limestone and to calculate the related theoretical recession rate. Graphic assessment, surface profiling, digital microscopy, infrared spectroscopy, and x-ray fluorescence are used to assess stone surface textures and degradation patterns associated with stone decay. The morphological analysis via surface profiling using silicon mould, digitization and statistical analysis of the roughness is proposed for the assessment of stone deterioration. In particular, the methodology is used for understanding stone morphological variations in relation to parameters such as sites, exposure (sheltered or exposed area), and location (overlooking a Canal or inner court). In relation to increasing rain amount and intensity, decreasing SO 2 and increasing NOx concentrations, theoretical limestone recession rate compatible with an urban environment (around 8 μm/year) are calculated. The morphological analysis of the sites evidences the role of the stone original texture and finish, the façade location and the specific exposure on the formation of crusts or eroded area. Buildings not recently restored (Ca' Bottacin and Ca' Bembo) present thick dendritic crusts, in particular on court side and in sheltered positions. Ca' Foscari surfaces, subjected to cleaning intervention after 2000s, show thin grey crust only in sheltered areas, reflecting the reduced presence of SO 2. Large eroded areas have been found on exposed surfaces in relation to the rain wash-out action and to high levels of NO x. Image 1 • Air quality and climate impact on limestone in Venice before and after 2000. • Evaluation of the atmospheric hazard to Istria Stone conservation during the 2000's. • Chemical, physical, morphological assessment of Istria stone in four venetian palaces. • Surface profiling of silicone moulds and statistical analysis of surface roughness. • Role of surface position, location, exposure in relation to a similar environment. [ABSTRACT FROM AUTHOR]