Environmentally-induced stone decay: the cumulative effects of crystallization–hydration cycles on a Lincolnshire oopelsparite limestone

An investigation has been undertaken at St Andrew’s church, Walpole St Andrew, Norfolk, to establish the underlying causes of the observed stone decay to the upper parts of the six stone piers. The stone decay was first recorded in the early 1930s. The salt-contaminated masonry within the church has been shown to undergo severe salt decay during the summer, with little damage occurring over the winter months. The south aisle piers have been shown to decay 2.5 times faster than the north aisle piers. Although crystallization–hydration cycles have been identified, the rate of decay is at its greatest when the cycling is relatively infrequent. This was not the expected trend. Furthermore, it has been shown that during extended periods where the ambient relative humidity is less than 75%, the rate of decay reaches a maximum. It is the length of this ‘drying’ period that apparently has the greatest influence on the rate of decay and could explain the significant difference in the rate of decay between the south and north aisle piers. The results have serious implications for passive conservation, where it is often recommended to lower the ambient relative humidity to well below the equilibrium relative humidity of the salt contaminant, to avoid crystallization–hydration cycles. Since, at the time of building, the church was situated on the coast, it is possible that the sodium chloride contamination occurred during the building process (1440–1520), particularly since the area was prone to sea-flooding at this time. Alternatively, the salt could have been applied as a treatment during the general restoration of 1897. Whatever the source of the salt, it seems likely that the ambient environment was changed by the insertion of a sealed floor in 1897, which could account for the onset of the salt decay.     

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The role of sports as a social status determinant for children.

This study was designed to examine children's attitudes toward the role of sports in determining social status, as well as the activities in which children prefer to participate. A total of 227 boys and 251 girls in Grades 4, 5, and 6 completed a questionnaire to determine which criteria were most important in determining personal, female, and male popularity. Personal popularity was answered by the girls and boys according to "what would make you well liked by your classmates." Female and male popularity was determined by asking both girls and boys to decide "what would make (girls, for female subjects, and boys, for male subjects) well liked by your classmates." A comparison of results from the Buchanan, Blankenbaker, and Cotten (1976) investigation and the present study indicated that, in the last 15 years, appearance has become more important and academic achievement less important in determining personal popularity for girls. For boys, the comparison revealed that sports have become more important and academic achievement less important in determining personal popularity. Boys reported sports to be the most important determinant of personal and male popularity and appearance as the most important determinant of female popularity. Sports and appearance became more important for boys with each higher grade level. Girls reported appearance to be the most important determinant of personal, male, and female popularity. For girls, appearance became more important with each higher grade level. A comparison of results from the Buchanan et al. (1976) and the present study indicated that the activities in which girls and boys preferred to participate have changed.(ABSTRACT TRUNCATED AT 250 WORDS)