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Several aspects of the biodeterioration of stone are reviewed, including general deterioration mechanisms, deterioration attributed to specific biological organisms, conservation case histories, and treatment options. The literature is cited with emphasis on historic monuments.

Microbiological agents, such as bacteria, actinomycetes, and fungi, degrade cellulose. The most severe deterioration in indoor environments is primarily caused by cellulolytic fungi, resulting in loss of fiber strength and actual material failure. Other microbial spoilage can occur as a result of the permanent staining from pigmentation and mycelial penetration by both cellulolytic and non-cellulolytic fungi, the latter using food sources ranging from starch sizing to surface dirt, and oils. Much has been written concerning biocidal testing against these microfungal agents from an industrial point of view; less from a conservation standpoint. This paper submits a limited review of current literature (c. 25 years) focusing on the information and its relevance for the conservator. The following topics related to cellulosic deterioration by fungal microbes are covered; 1. current theories about the mechanism of cellulolytic attack; 2. biocides which may be employed in fungal control; and 3. choice of environmental conditions as a means of static control of fungal biodegradative agents. An annotated reference list is provided.

Scanning electron microscopy and energy dispersive X-ray spectrometry (SEM-EDS) have been employed along with the light microscope to describe some metal threads made of proteinaceous substrates taken from museum textile collections. The textiles are said to originate in Central Asia, Western Asia, and Syria or Egypt, thirteenth/fifteenth century AD. This study extends the set of data obtained in an earlier study of threads from the same time-period. A general methodology for the examination of these types of metal threads is proposed.

2-Aryl-N,N'-dimethyl-1,3-imidazolidines and 2-aryl-1,3-dioxolanes were subjected to 70 eV spectral analysis. Fragmentation pathways for both series of compounds are suggested. Aryl vs. benzylic hydrogen fragmentations were subjected to Hammett σ+ ρ plots. Incipient charge on the benzyl carbonium ion was stabilized by electron donating groups in both series of compounds. Dioxolanes were more sensitive to substituent effects (ρ = −0.639) than the imidazolidines (ρ = −0.251) implying that the positive charge on the fragmenting ion is more localized at the benzylic position of the imidazolidines than of the dioxolanes.

Stress relaxation master curves were obtained for polystyrene, polymethyl methacrylate, and polyvinyl chloride, all plasticized with dioctylphthalate. The plasticized polyvinyl chloride results were quite different from the others, and this was tentatively ascribed to borderline crystallinity.

Samples of modern wool, silk and cotton woven fabrics were mordanted with five common dyeing mor- dants: potassium aluminum sulfate, cupric sulfate, ferrous sulfate, stannous chloride and potassium dichromate. Samples were observed by scanning electron microscopy (SEM) and metallic elements detected by energy disper- sive X-ray spectrometry (EDS). The results and limitations of the detection process are discussed and compared to other analytical procedures. The application of this proce- dure to historical textiles for analysis of metallic mordants and certain dyes is discussed.