The impact of electric overhead radiant heating on the indoor environment of historic churches

The impact of electric overhead radiant heaters on the microclimate, air flows, transport and deposition of suspended particulate matter (SPM) was monitored between March 2004 and March 2005 in the historic churches of Saint Michael Archangel in Szalowa and Saint Catherine in Cracow (Poland). The measurements show that although irradiation at the floor level increases temperature and reduces relative humidity in the interior of the church, the effect out of the heated zone and for the surfaces sheltered from irradiation is very limited, i.e. their extent is comparable with natural fluctuations inherent to the local climate of the church. The radiant heaters proved to generate little convectional flow of the air. Therefore, the heating system was not found to increase the concentration of SPM indoors; in particular, no re-suspension of particles already present in the church was observed. This work has demonstrated that the overhead radiant heaters are capable of providing localised heat to the areas where people congregate without adversely affecting painted walls and the works of arts displayed in churches. Care, however, should be taken that sensitive works of art are not exposed to the direct infrared radiation.     

Comparison of hot-air and low-radiant pew heating systems on the distribution and transport of gaseous air pollutants in the mountain church of Rocca Pietore from artwork conservation points of view

The concentrations of CO₂, CO, formaldehyde (H₂CO) and water vapour were simultaneously monitored in various sections of a mountain church situated in the village of Rocca Pietore in the Italian Alps. The performance of a conventional, hot-air heating system and a novel design for heating the church, consisting of low-temperature heating elements, such as electrically heated pews and carpets, were compared for the supply, transport and removal of gases, the deposition and/or transformation of which may affect the preservation of displayed works of art. Experiments with sulphur hexafluoride (SF₆) tracer-gas showed a considerable influx of external air through the hot air carrier ducts of the old heating system, and also the leakage of the internal air mostly via the apertures of the doors. The ventilation rates for the total volume of the church with the hot-air heating system (on for 1.5 h), the new heating system (on for 2 h), and without heating were calculated to be 0.25, 0.18, and 0.13 h⁻¹, respectively. Without heating, a nearly homogeneous distribution of gases has been observed along both the horizontal and the vertical cross-sections of the church. Immediately after switching on the hot-air heating system, the levels of CO₂ and water vapour showed a sharp increase. After turning this system off, the levels of gases showed a slow fall and they developed a highly non-homogeneous spatial distribution indoors for many hours. In the upper region of the church, being airtight, higher concentrations of the pollutants could be detected. The low levels of CO and H₂CO, mostly originating from incense burning during services, were correlated to that of CO₂. The hot-air heating system has been proved to present a potential deterioration risk to artworks, as it increases the supply, transport and deposition probability of air pollutants. On the other hand, the novel, symmetrical heating system eliminates these undesirable effects, thus its application is advantageous to all churches involved in the preservation of works of art.     

An advanced church heating system favourable to artworks: A contribution to European standardisation

The European project Friendly-Heating (FH): comfortable to people and compatible with conservation of artworks preserved in churches addressed the problems caused by the continuous or intermittent heating of historic churches, which disturbs the microclimatic conditions to which the building and the artworks preserved inside have acclimatised. As thermal comfort and the preservation of artworks often conflict with each other, a balance between the two needs is necessary. The proposed heating strategy is to provide a small amount of heat directly to people in the pew area while leaving the conditions in the church, as a whole, undisturbed. This novel heating system is based on some low-temperature radiant emitters mounted in a pew to provide a desirable distribution of heat to the feet, legs and hands of people occupying it. Due to little heat dispersion, this novel system not only significantly reduces the risk of mechanical stress in wooden artworks and panel or canvas paintings, fresco soiling and cyclic dissolution-recrystallization of soluble salts in the masonry, but is energy-efficient. The detailed environmental monitoring was conducted in the church of Santa Maria Maddalena in Rocca Pietore, Italy over a 3-year period to verify the performance of the novel heating system in comparison to the warm-air system that was active earlier in the church. The methodology and results of this comprehensive and multidisciplinary study were included in three draft standards of the European Committee for Standardisation intended for use in the study and control of environments of cultural heritage objects.     

Control of indoor environments in heritage buildings: experimental measurements in an old Italian museum and proposal of a methodology

This paper describes some results from an experiment carried out regarding a procedure to be adopted for temperature and R.H. monitoring of indoor spaces designed for exhibiting events, such as museums and similar institutions. The monitored data employed in this study has been collected by the Department di Ricerche Energetiche ed Ambientali of the Università degli Studi di Palermo in co-operation with the Regional Gallery ''Palazzo Abatellis'' of Palermo. The study analyses a simple method for characterising the environmental quality of museums so as to ensure the optimal conservation of works of art. This methodology is based on the procedure (where thermal and hygrometry parameters are concerned) proposed by an Italian standard rule. A new technique, firstly applied to the industrial environment, based on the passive reactive monitoring of proper coupons is also proposed for monitoring air quality in museums. The methodology adopted, has been applied to two survey campaigns which were carried out at a distance of 5 years. This shows the two aspects of thermal-hygrometry and levels of indoor air quality aimed at preserving works of art. The future developments of this work are oriented towards the definition of guidelines in support of those responsible for the conservation of works of art and improvements in the quality of environments for artwork conservation and for the comfort of visitors through the use of proper HVAC systems.     

Daily natural heat convection in a historical hall

The use of numerical simulation methods for the Cultural Heritage is of increasing importance for the analysis, conservation, restoration and appreciation of works of art. This is particularly important when their preservation and planned maintenance is the primary aim. Today museums, and particularly historical buildings converted to museums, should be considered as places where precious artefacts should have first-rate protection and conservation. It is a question of solving the compromise between protection, conservation and comfort for works of art and/or visitors, with the consequence that preservation and planned maintenance criteria must prevail over use requirements. Refurbishment and conservation of a building, and requirements for visitor presence and works of art need different thermo-physical indoor parameter values. The present paper concerns the thermal and air velocity analysis of the Salone dei Duecento (the Hall of the Two Hundred of the Palazzo Vecchio (Old Palace)) in Florence. In this paper an appropriate transient 3D model by Computational Fluid Dynamics (CFD) software based on the finite element method (FEM) was used. Variations and interaction between indoor and outdoor microclimatic conditions, and thermo-physical behaviour of the building connected to lighting, visitor presence and cooling–heating fan coils system were considered. The 3D modelling method provided by the present paper can be applied to several situations where there is interaction between outdoor and indoor climate variations and the building structure. It can be very useful for defining measures to preserve tapestries, understanding deterioration processes, and developing new conservation techniques and strategies for care and exhibition.     

Transport and deposition of airborne pollutants in exhibition areas located in historical buildings–study in Wawel Castle Museum in Cracow,Poland

Historical buildings and castles that have been turned nowadays into museums, as an exhibition area for precious cultural heritage (CH) items, need more attention since they are CH objects by themselves. Moreover, the preservation techniques require often, significant interventions; however such changes are not always possible or are very limited. The aim of the present study was to investigate the influence of outdoor air pollution on the composition of particulate matter and gases inside the museum of Wawel Castle in Cracow, Poland. During this study a combination of micro and trace analysis techniques were applied, including energy dispersive X-ray fluorescence (EDXRF) and electron probe microanalysis (EPMA). An intensive transport of air pollutants coupled with accumulation of the particles inside the museum was noticed (considerably higher in winter than summer). A high content of carbon and organic matter agglomerated with inorganic particles was determined. Those particles are of special concern because of their adhesive properties and reactivity. It was also noted that the conditions inside the museum favour the reaction of the particles with gaseous pollutants. It was especially the case for nitrate particles.     

Significance of studying the petrography and mineralogy of the geological environment of old rupestrian churches to prevent their deterioration. A case study from the South Carpathians

This paper provides new insights into understanding the causes of deterioration of the Corbii de Piatra rupestrian church and shows the significance of studying the geological environment of historical rock-cut settlements when undertaking preservation and restoration actions. The Corbii de Piatra church is one of the few rupestrian churches remaining in Romania and is an important part of the country's heritage. The church is carved in a stratum of polymictic sandstone of Oligocene age, which is part of the Getic Depression, located in the southern part of the South Carpathians. In the 14th century the interior walls of the church were decorated with mural paintings of a high artistic value. Over the centuries, the church's walls and mural paintings have been negatively affected by a series of physicochemical processes. These processes were studied through field investigations and laboratory analyses carried out between October 2007 and November 2010. The investigations revealed that tectonic fissuring and the structural anisotropy of the rock facilitate the infiltration of meteoric water through the walls into the interior of the church, from north to south, maintaining a high-level of humidity in the northern wall and in the interior of the church. The most harmful effects observed were: (i) the partial hydrolysis of the feldspars through reaction with water from the pores, producing a friable mass of phyllosilicates which led to a superficial disaggregation of the rock and to a diminished cohesion between the rock and the mortar of the fresco, (ii) the reprecipitation of the gypsum as efflorescences on the northern wall and ceiling, covering the mural painting in localized areas, as a result of the transportation of the gypsum by water from the upper strata, (iii) the alteration of the cinnabar pigment, as a result of water penetration by diffusion through the fresco from the wet rock to the pictorial layer (the secondary effect observed being the formation of sulfuric acid, which further reacted with the carbonate from the fresco to form gypsum), (iv) the development of biotic crusts, predominately algal, on the interior wet walls, which, facilitated by the permanent high humidity and the semi-obscurity of the interior of the church, have covered large surfaces of the fresco. Compared to the interior, the exterior vertical walls have been exposed to prolonged daily and seasonal variations of temperature and humidity. These variations have caused repeated variations in the volume of the sandstone, leading to contraction fissuring and peeling of the vertical walls. Any future procedures that might be used to conserve the church should strive to reduce the humidity of the sandstone in the interior walls.     

Ground penetrating radar (G.P.R.) surveys applied to the research of crypts in San Sebastiano's church in Catania (Sicily)

The aim of the present paper is the identification of natural or anthropic buried cavities under the church of St. Sebastiano in Catania (Sicily). To this purpose Ground Penetrating Radar (G.P.R.) surveys were performed on the pavement of the church and three in situ drillings were carried out outside the church. Through the G.P.R. investigation, the existence of hidden structures was revealed; the results obtained by in situ drillings allowed a detailed characterization of the most superficial layers of the ground.     

The Re-emergence of The Forty Martyrs of Sebaste in the Church of Saint Peter and Paul,Famagusta, Northern Cyprus

This article presents the first study of a painting, possibly the Forty Martyrs of Sebaste, which has been concealed for over 500 years, and which has, this century only, re-emerged through plaster removal in the church of SS. Peter and Paul in Famagusta, N. Cyprus. Though very badly damaged the painting, which has remained undocumented and unstudied in the history and art history of Cyprus, may offer vital clues concerning internationalism and cultural interaction in Cyprus in the 14th and 15th centuries. It also offers specialists a rare glimpse at Italian ecclesiastical wall painting from this rich period in western art history, and makes clear the intellectual loss that might be felt if some basic conservation processes are not begun soon. Lastly, in the light of the changing political situation in that island it invites scholarship in a range of disciplines to the church and to other historic landmarks within the old city walls.     

Art Museums: Collections, Deaccessioning and Donations

This paper looks at three issues: the functions of art museums, the role of deaccessioning in this context and the importance of donations of works of art in contributing to the collection function. Donor restrictions it is argued should not be allowed to unduly influence the policy of an art museum, including that in relation to deaccessioning: this is especially the case given that often the state has paid, in the form of a tax expenditure, for the bulk of such donations.     

Swelling damage in clay-rich sandstones used in the church of San Mateo in Tarifa (Spain)

This study shows that the sandstone used in the construction of the Church of San Mateo in Tarifa (Cádiz, Spain) is highly sensitive to processes of decay because of a combination of factors that are intrinsic and extrinsic to the material. The mineralogy, texture and porous system of the sandstone and the proximity of the church to the sea all play a part in these processes. X-ray diffraction reveals that there are interstratified chlorite/smectite clays among the minerals that make up the rock. These mixed layer clays have been shown to undergo hydric expansion. This phenomenon may be accompanied and augmented by the presence of NaCl which acts as an electrolyte in osmotic swelling processes. Two varieties of sandstone were used in the construction of the church, namely grey sandstone and brown sandstone. The latter is more porous and undergoes greater hydric expansion, showing a higher degree of deterioration. Ultrasound analysis has demonstrated that both varieties are anisotropic because they contain bedding planes and are affected by the preferred orientation of the phyllosilicates in the rock. The anisotropic nature of these stones was confirmed by capillary suction tests. The capillary front reaches a relatively low height which means that when water is absorbed, the anisotropic textural properties combined with the presence of chlorite–smectite mixed layers in the sandstone result in mechanical (shear) stress between the first few centimetres of the wet stone and the dry area behind. The latter effect favours the development of flakes, so causing the decay of the ornamental stone and the church façade.     

CFD application to optimise the ventilation strategy of Senate Room at Palazzo Madama in Turin (Italy)

Over the last years, there was an increasing interest in keeping suitable microclimatic conditions for the preservation of artefacts: the artefacts preservation requirements may diverge from those of the museums visitors, willing to enjoy the works of art in a situation of psycho-physical wellness. The HVAC designers and engineers will have then to cooperate closely with the curator, in order to define a compromise between conflicting environmental performance requirements. In particular at the stage of air-conditioning system design or retrofit, it is extremely important to carry out a series of preliminary analysis to evaluate and monitor the existing environmental conditions and to anticipatory simulate and predict the post-intervention conditions. To this aim, advanced fluid-dynamic investigation tools (Computational Fluid Dynamic [CFD] techniques) enable to deal with the specificity of such topics and provide a useful decision-making support.     

Ammonium oxalate treatment: Evaluation by μ-Raman mapping of the penetration depth in different plasters

This study is focused on the evaluation by μRaman mapping of the penetration depth achieved by ammonium oxalate treatment in different plaster specimens, a hot issue in the conservation field. The role of the carbonatic aggregate particles and the influence of the different variables of the treatment on the penetration depth and on the distribution of the newly-formed phase (whewellite) have been ascertained. Based on the results of μRaman mapping, analyses with Field Emission Scanning Electron Microscopy have been carried out in order to observe the whewellite crystals and the carbonatic aggregate particles involved in the reaction with ammonium oxalate.     

The Elasticity of Thought: A Note on the Drive in Worringer and Freud

Abstract

The essay approaches recent discussions of ‘life’ and biopolitics from the historical context of early 20th century German vitalist thought. By closely analysing the concept of the ‘drive’ in art historian Wilhelm Worringer's Abstraction and Empathy (1908) and Sigmund Freud's Beyond the Pleasure Principle (1920), the essay shows how the paradoxes of those texts prefigure and contribute to the contemporary problematic of ‘life’ in theoretical discourse across the humanities. In Worringer and Freud, the drive is an ‘elastic’ concept stretching beyond – and yet constitutive of – the epistemological object (‘life’) that it is called upon to describe. The distortion of the drive in each author's thought – from an impulse of organic vitality to a principle of inorganic primordiality – manifests the contradictory ‘life’ of vitalist concepts themselves in their elastic potential for transformation, regression and contradiction.     

Non-destructive monitoring methods as indicators of damage cause on Cathedral of St. Lawrence in Trogir,Croatia

Durability is one of the most important engineering properties of cultural heritage monuments. For the purpose of the preservation of structures for future generations, the causes of damage should be determined for the proper choice of type and location of strengthening. The condition of the foundation is difficult to determine without an extensive investigation which is critical because most often the cause of damage is found in such foundations. Geotechnical investigation techniques require the damage and destruction of a building's surroundings or the damage of a foundation with a boring device. Non-destructive methods, such as geophysical methods, are less reliable and the results of such investigations must be combined with the results of subsurface exploration. This paper is a presentation of results achieved through the monitoring of the activity of a number of joints on the Cathedral of St. Lawrence in Trogir, Croatia, which is a cultural heritage monument protected by UNESCO. Excavations for the purpose of flagging replacement in the zone around the east frontage were made in 1979. A probe beneath the main apse uncovered a water cistern where the connection between the mid and north apses is located, and instead of a staggered foundation, a wall with a depth of more than 2.2 m beneath the flagging was discovered. With respect to the given that churches were built on existing ones, it is possible to assume that this is a wall of the late-antiquity church described by Constantin Porfirogenet in the 10th century, built on and later adapted to the foundation for the new structure. The displacement in time of the construction elements of the cathedral were measured and recorded using non-destructive methods. Fissure displacement behaviour, air temperature and air humidity were monitored. The monitoring of the air humidity did not lead to any useful conclusion, so it was quickly dismissed. Observations of data were performed during two periods with an interruption between the two caused by insufficient monetary resources. Data from almost 8 years of continuous measuring are available. The aim of this paper is to present the data of the measured fissure displacements which were correlated with air temperature changes and mathematical models which were based on statistical analysis. Correlation coefficients show that the analysed fissures react to the air temperature changes with different intensities. The obtained data lead to the conclusion that the causes of the structural damage are not found within a displacement or failure of the foundations. Instead, the causes of the damage were found in other parts of the structure.     

Holographic applications in evaluation of defect and cleaning procedures

Holographic interferometry (HI) was chosen as the diagnostic tool to support non-destructive identification of structural defects commonly found in numerous art conservation problems. Holographic recording provides the highest information content of the concerned artwork and by implementation of a portable pulse laser the procedure becomes vibration isolation free for use outside the laboratory. Nowadays, it is comprehensively appreciated from art conservators that detailed structural knowledge is essential when conservation of precious artworks is concerned. The versatility of a holographic interferometer when used to acquire explicit structural information of art objects is demonstrated here in characteristic cases.     

一剪一贴见神功——记王浣清的剪贴画

在丽水莲都区,有一位痴迷于花鸟虫鱼的剪纸人,她就是退休教师王浣清。凭着一把剪刀,一罐浆糊,她在传统的剪纸基础上,推陈出新,剪出了一个精彩缤纷的世界。中国美术研究院副院长、国家一级美术师刘频华在看了她的作品之后大加赞叹,认为老人的作品有别于传统剪纸作品,独具特色,应该叫“剪贴画”。     

Are Multiple Art Markets Rational?

We advance and subsequently test the proposition thatmarkets for fine art are rational, namely, that, inthe determination of price, traders make use of allrelevant art historical and critical information, asrevealed by hedonic content analysis, as well as allinformation on authenticity of the works offered forsale. If true, the proposition has consequences forpublic policy. Museums optimize choices among art historicallysignificant authentic paintings distributed asstochastic rare events in the tertiary market for art. Such paintings have few, if any, art historicallyequivalent substitutes, causing the demand for suchworks of art to be extremely inelastic. Museums tendto buy at the top of the information curve; payingprices which exceed market averages for similar art. As a result, society pays the cost of institutionalrisk aversion. In contrast, collectors often purchaseart before all art historical information is complete,and often earn a reward for assuming a risk due toincomplete information (Singer, 1991; Pomerhene, 1994).Collectors who can borrow to accumulate the highestcategory art can consume the services of their artcollection at zero cost. Stochastic transferfunctions fitted to time series of sales volume at thetwo top international auction houses confirm thehypothesis that the highest category of art is a quasisubstitute for financial instruments (liquid wealth).     

What Has the Visual Artist's Rights Act of 1990 Accomplished?

This paper presents an economic analysis of the Visual Artist's Rights Act of 1990 (VARA) which provides attribution and integrity rights, commonly called moral rights, for defined types of artistic works. The paper shows that these laws may actually harm artists by adding contracting and transaction costs in the art market. For most works, these costs will be trivial because collectors have a strong self-interest in preserving works in good condition. These costs are more likely to be significant, however, for works subject to destruction or alteration in the future, such as site-specific works and works installed in buildings, because purchasers will require waivers rather than risk violating the Act. The paper also examines the few cases that have been litigated under VARA. Consistent with the economic model, these cases involve large-scale works by relatively unknown artists that have been destroyed by building projects. Finally, the paper presents an empirical analysis of state moral rights laws. Nine states enacted these laws prior to VARA. These laws had no significant effect on artist earnings but a positive and significant effect on the number of artists living and working in the state.