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This chapter presents original arguments for the view that Boyle regarded chemical properties as being dispositional, relational, and emergent properties. The chapter begins by discussing the hierarchy of properties in Boyle’s chemical ontology and Boyle’s notion of sensible properties as being dispositional and relational. Both of these sections are informed by Peter Anstey’s discussion of these topics. The chapter then moves beyond Anstey’s discussion by arguing for the view that Boyle regarded chemical properties as dispositional, relational, emergent, and supervenient properties. The chapter cites many examples from Boyle’s writings to demonstrate that he considered chemical properties to display the various features that are required for emergence, that is, supervenience, non-summative difference, and underdetermination. After this extensive discussion, the chapter concludes by establishing that Boyle also considered cosmical qualities as dispositional and relational, thus demonstrating the considerable philosophical sophistication of Boyle’s natural philosophy and of his entire experimental programme.

This chapter discusses the mineralogy of asbestos. Topics covered include mineralogical and geological features, air particulate burdens and respiratory tract response, occurrence and physical-chemical properties of chrysotile, and occurrence and physical-chemical properties of amphiboles.

The use of the squid axon as a model system for the study of anaesthetic mechanisms is described. Effects are divided into actions on the voltage-gated Na and K channels and actions on a voltage-independent K conductance system of the nerve membrane. Inhibition of axonal function by anaesthetics arises largely from effects on the Na channel. The precise nature of these effects varies with the physico-chemical properties of the anaesthetic considered, but certain general principles emerge. Small non-polar anaesthetics tend to increase the resting fraction of Na channels in the inactivated state. The actions of certain fluorinated anaesthetics and convulsants on the squid axon are described in the context of the close relationship between anaesthetic and convulsant actions. At low concentrations these molecules all appear capable of increasing axonal excitability and reducing the threshold for action potential generation. This action is related to the inhibition of a resting K permeability system in the axon membrane. The anaesthetics and convulsants can be distinguished in this axonal model on the basis of their relative potencies for inhibition of resting K permeability and Na channels. Convulsants appear to be characterized by an ability to inhibit the resting K permeability, but are inactive, even at high concentrations, on the Na channel. It is suggested that these properties may parallel the wider biological actions of anaesthetics and convulsants including actions on the central nervous system.

The distribution of plants and animals found on wetlands is influenced by environmental factors that operate at various scales and determine what organisms will be found in a given wetland. Ultimately, the recruitment, population dynamics, and production of all wetland organisms are controlled by local environmental conditions. In any given climatic region, the major environmental variables affecting wetlands include the chemical and physical properties of water and the physical and chemical properties of the soil. This chapter explores the physical and chemical environments of wetlands. It first considers the most ecologically salient properties of water such as solvency, transparency, high density, viscosity, and specific heat. It then examines wetland hydrology, including water budgets and water regimes, as well as secondary environmental gradients (light, oxygen, temperature) generated by plant canopies and their significance for animals. Finally, the chapter discusses the properties of soils found in wetlands, with an emphasis on anaerobic soils.

Habitats show great variability in their physical and chemical properties, but even so they support a wide variety of animal species. Fluctuations in environmental temperature, salinity, and oxygen levels are normally accommodated by animals without ill effect, unless the changes are large and challenging. If the environmental changes occurring at the animal's exterior were experienced by the cells and tissues within the animal, they would be badly damaged if it were not for physiological systems that maintain relatively constant conditions in the animal's internal environment. The capacity of animals to recognise perturbations of their physiological systems and then restore them to normal is referred to as homeostasis. Sensory systems inform on events or changes in the environment, and responses such as movement, feeding, reproductive behaviour, or escape are orchestrated by the nervous and endocrine systems.

This chapter examines the organic-rich soil profiles of peat. It first considers the process of peat formation by organic matter through sedentation and sedimentation before comparing the organic versus mineral matter content of peat. It then describes three commonly used techniques for sampling the peat profile: the Russian, Livingston, and Hiller side-opening samplers. It also looks at the botanical composition of peat and its degree of decomposition, physical properties, and electrochemical and chemical properties. Finally, the chapter discusses the interrelationships of peat properties and the histosol and organic soil of peat.

It has been seen in the previous chapter that, when organic reducing substances are in contact with soils, iron and manganese oxides of the soil can be reduced, producing ferrous and manganous ions. This reduction process is of particular significance for variable charge soils. This is because the contents of iron and manganese oxides in these soils are higher than those in constant charge soils, and therefore there is the basis for the production of large amounts of ferrous and manganous ions. On the other hand, the low pH of variable charge soils is one of the favorable factors in the reduction of iron and manganese. Hence, the possibility exists for the production of the reduced form of these two elements exists even under well-aerated conditions, provided that the soil contains organic matter. It is for these reasons that iron and manganese can actively participate in chemical reactions in variable charge soils in the form of ions, and they are of great significance in both soil genesis and plant nutrition. As a matter of fact, many reports have shown that the amount of manganous ions in strongly acid soils is so high that the toxicity of manganese may be one of the causes for the poor growth of plants. In this chapter, after the elucidation of the reduction and dissolution of iron and manganese, emphasis of discussions will be placed on the chemical equilibria of the two kinds of ions. Finally, the regimes of the two ions in variable charge soils under field conditions will be described. The solubility of iron oxides in soils is extremely low. The solubility product of Fe(OH)3 is about 10-38. Therefore, the concentration of Fe3+ ions in solution is only 10-8 M even at a pH of 4, if the concentration is determined solely by the solubility of the oxides. Similarly, the quantity of Mn4+ ions due to the dissolution of manganese oxides is also very small. On the other hand, because the solubility products of Fe(OH)2 and Mn(OH)2 are about 10-16 and 10-13, respectively, after reduction, ferrous and manganous (in this chapter the latter is simply referred to as manganese) ions can exist stably in soils.