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This chapter examines the work of entrepreneurs and industrialists from the mid-1770s through the 1790s who competed for supremacy in developing chemical techniques by which to replicate chemically unstable academic paintings. Highlighting the involvements of many chemical replicators with radical politics, the chapter places lithography (the best known of the period’s chemical-imaging innovations), encaustic, and enamel painting in relation to the chemical scandal of the “Venetian Secret” as made public in 1797. Therein, Benjamin West and other leading Academicians had pursued a fraudulent compilation of painting techniques purportedly used by Titian and other Venetian masters. The chapter expands to consider a host of lesser known chemical technics including “pollaplasiasmos,” James Watt’s copying machine and the interventions into the philosophy of time advanced by Thomas Wedgwood, purported “first inventor” of photography. The chapter argues against the familiar identification of Thomas Wedgwood’s chemical research with photography.

Examines the relationships between Shanghai artists and their public and the establishment of these relationships through Shanghai’s growing mass media outlets. By exploiting the city’s burgeoning newspaper and publishing industries, artists promoted themselves as public figures and marketed themselves, their products and activities; through the mass media, they were able to access audiences on local, national and even international levels. By using newspaper advertising and articles, guide books, popular periodicals and collected writings, this chapter reveals the formation of the art world’s public image, promoted for consumption by an urban audience and mass readership.

Focuses on the active participation of artists in Shanghai’s publishing industry, specifically their contributions to the treaty port’s illustrated books and magazines. Capitalizing on the new technology of lithography, Shanghai rose swiftly to become China’s center of publishing in the late Qing, and pictures by Shanghai artists featured prominently in the city’s new mass media. By using case studies of several publishing projects from this period, including illustrated books and artist designs for magazine inserts, this chapter investigates how artists expanded their reputations, accessed a large urban readership and developed a mode of lithographed imagery that addressed a popular audience in their accessibility, topicality and playfulness.

Numerous medical applications have been developed for siloxane polymers. Prostheses, artificial organs, objects for facial reconstruction, vitreous substitutes in the eyes, tubing and catheters, for example, take advantage of the inertness, stability, and pliability of polysiloxanes. Artificial skin, contact lenses, and drug delivery systems utilize their high permeability as well. Such biomedical applications have led to extensive biocompatability studies, particularly on the interactions of polysiloxanes with proteins. There has been considerable interest in modifying these materials to improve their suitability for biomedical applications in general. Advances seem to be coming particularly rapidly in the area of high-tech drug-delivery systems. Figure 10.1 shows the range of diameters of Silastic medical-grade siloxane tubing available for medical applications. The smallest tubing has an internal diameter of only 0.012 inches (0.031 cm) and an outer diameter of only 0.025 inches (0.064 cm). Such materials must first be extensively tested (sensitization of skin, tissue cell culture compatibility, implant compatibility). There has been considerable controversy, for example, over the safety of using polysiloxanes in breast implants. The major concern was “bleeding” of low molecular polysiloxanes out of the gels into the chest cavity, followed by transport to other parts of the body. The extent to which “bleeding” occurred and its possible systemic effects on the body were argued vigorously in the media and in the courts, and led to restrictions on the use of polysiloxanes. In the case of controlled drug-delivery systems, the goal is to have the drug released at a relatively constant rate (zero-order kinetics) at a concentration within the therapeutic range. It is obviously important to minimize the amount of time the concentration is in the low, ineffective range, and to eliminate completely the time it is in the high, toxic range (figure 10.2). Figure 10.3 illustrates the use of polysiloxanes in such drug-delivery systems. The goal mentioned is approached by placing the drug inside a siloxane elastomeric capsule, which is then implanted in an appropriate location in the body. The drug within the capsule can be in the free state, in a fluid suspension, or mixed or dissolved into an elastomeric matrix.

The first part of chapter 4 turns to the work of William Lassell, which will underscore a characteristic of observational procedures: their dependence on the instrumental means available. This emphasis will go into further highlighting the strategies used by our earlier observers in their attempts to transcend their apparatuses and sites. Part 2 of the same chapter will investigate a procedure used by Wilhelm Tempel, which was developed particularly with an eye to artistic skill, technique, and the final lithographed product. In the face of the rising number of “contradictory” representations of the nebulae at the end of the century, Tempel proposed that observers draw only what they see and eschew the inclusion of the mind; it is what this proposal meant for him and how he proposed to achieve it that will be explored.

By the 1830s, the urban renewal project discussed in the previous chapter only further revealed the intractable messiness of the urban landscape. A decade of gentrification exacerbated anxiety about whether the city’s sites and edifices could compete with surrounding topographical and human congestion. The champions of improvement sought to ease their doubts by commissioning images that abstracted, obscured, or shrank into insignificance the disorder surrounding urban landmarks. Yet even as these ideal representations of the city proliferated, Bostonians questioned whether their fellow spectators saw moral landmarks as intended. A middle-class culture of novels, guidebooks, periodicals, plays, and other sources introduced a new typology of spectators—the connoisseur and the poseur, the vista seeker and the speculator, the libertine and the sentimentalist—who revealed their true characters through their divergent reactions to the city’s monuments, parks, galleries, paintings, and sculptures.

Because of the great importance of the surface properties of the polysiloxanes, this topic is treated separately in this chapter. Hydrophobic polysiloxanes having simple aliphatic or aromatic side groups have surfaces that show essentially no attraction to water. In fact, polysiloxanes can serve as water repellants. This property is very useful for applications such as protective coatings on historical monuments and for controlling the surfaces of other polymers, sensors, and quantum dots. Hydrophobic surfaces can be readily regenerated if the surface becomes damaged. Regeneration occurs by rearrangements of the polysiloxane chains so that the hydrophobic methyl groups are once again covering the surface. The flexibility of the siloxane chain backbone facilitates this process. It is also possible to prepare hydrophobic films using methyl-modified siloxane melting gels. Glass surfaces or wool fibers can be coated with polydimethylsiloxane (PDMS) to make them more hydrophobic. In some cases, it is necessary to modify a polysiloxane surface to make it hydrophilic or hydrophobic. Hydrophobization is one aspect of the general topic of modifying and managing the properties of polymer surfaces. An important example involves soft contact lenses that contain PDMS, which is often used because of its very high permeability to oxygen, which is required for metabolic processes within the eye. Such lenses do not feel comfortable however because they do not float properly on the aqueous tears that coat the eye. There are a number of ways to modify the surfaces. There is even a way to make “unreactive” silicones react with inorganic surfaces. In some applications it is useful to have hydrophilicity in the bulk of the polymer instead of just at the surface. One way of doing this is by simultaneously end linking hydrophilic poly(ethylene glycol) (PEG) chains and hydrophobic PDMS chains. Another way is to make a PDMS network with a trifunctional organosilane R’Si(OR) end linker that contains a hydrophilic R’ side chain, such as a polyoxide. Treating only the surfaces is another possibility, for example, by adding hydrophilic brushes by vapor deposition/hydrolysis cycles. Such hydrophilic polysiloxanes can also serve as surfactants.

Numerous medical applications have been developed for siloxane polymers. Prostheses, artificial organs, objects for facial reconstruction, vitreous substitutes in the eyes, tubing and catheters, for example, take advantage of the inertness, stability, and pliability of polysiloxanes. Artificial skin, contact lenses, and drug delivery systems utilize their high permeability as well. Such biomedical applications have led to extensive biocompatability studies, particularly on the interactions of polysiloxanes with proteins. There has been considerable interest in modifying these materials to improve their suitability for biomedical applications in general. Advances seem to be coming particularly rapidly in the area of high-tech drug-delivery systems. Figure 10.1 shows the range of diameters of Silastic medical-grade siloxane tubing available for medical applications. The smallest tubing has an internal diameter of only 0.012 inches (0.031 cm) and an outer diameter of only 0.025 inches (0.064 cm). Such materials must first be extensively tested (sensitization of skin, tissue cell culture compatibility, implant compatibility). There has been considerable controversy, for example, over the safety of using polysiloxanes in breast implants. The major concern was “bleeding” of low molecular polysiloxanes out of the gels into the chest cavity, followed by transport to other parts of the body. The extent to which “bleeding” occurred and its possible systemic effects on the body were argued vigorously in the media and in the courts, and led to restrictions on the use of polysiloxanes. In the case of controlled drug-delivery systems, the goal is to have the drug released at a relatively constant rate (zero-order kinetics) at a concentration within the therapeutic range. It is obviously important to minimize the amount of time the concentration is in the low, ineffective range, and to eliminate completely the time it is in the high, toxic range (figure 10.2). Figure 10.3 illustrates the use of polysiloxanes in such drug-delivery systems. The goal mentioned is approached by placing the drug inside a siloxane elastomeric capsule, which is then implanted in an appropriate location in the body. The drug within the capsule can be in the free state, in a fluid suspension, or mixed or dissolved into an elastomeric matrix.