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This chapter follows the evolution of rights to use or enjoy streams and lakes. It distinguishes legally ‘land-based’ systems from those that are ‘use-based’. Tracing the alternation or cycling of these two systems in four countries, and beginning with a brief survey of Roman water law it shows that that medieval English law regarded rights over fresh water as a continuation of rights over the adjoining land. A change to use-based rights began when mill-owners ‘demanded’ that their water rights be interpreted by the courts to protect private title to a flow; this was accomplished in the Industrial Revolution by recognizing priority in use. This prior-use concept was found inadequate and in the next phase the English courts swung back to a land-based right, adopting ‘natural’-flow and ‘reasonable’-use criteria to decide which cities and factories should have rights. The chapter follows these phases abroad. It describes the western-lands invention of the appropriative-rights doctrine in the US, and its adaptation elsewhere. Throughout, the chapter also refers to changes in ‘prescriptive rights’ to water, distinguishing them from those in the prior-use and prior-appropriation phases.

This chapter examines the effectiveness of civic attempts to regulate and improve the urban environment against a background of population change and epidemic plague. The maintenance of communal buildings such as the walls, the implementation of building regulations, and the attempts to preserve green spaces and control livestock and industrial activities are all examined. By communal and charitable efforts the citizens were able to ensure a piped supply of fresh water. The chapter demonstrates the Londoners' concern to ensure that their city was clean and healthy.

Freshwater habitats are filled with abundant animal life from numerous phyla. Because the osmotic concentration of fresh water is extremely low compared to both extracellular and intracellular fluids, all freshwater animals are hyper-regulators. The influx of water across the integument presents a difficult and costly physiological challenge. Freshwater animals have evolved numerous mechanisms for producing very dilute urine as a means of ridding themselves of this excess water. A second challenge is the requirement to obtain ions from an environment in which ionic concentrations are exceptionally low. Ion uptake is achieved by specialized transport processes in both the integument and the gut. Examples from both invertebrate and vertebrate groups are provided to illustrate the physiological and morphological diversity that exists in freshwater organisms.

This chapter explores what is known about how amphibians deal with extreme environmental situations, beginning with aquatic environments, both fresh water and marine. It then describes life in extreme terrestrial and underground environments. The next section deals with overwintering in both aquatic and terrestrial environments, and discusses the particular stresses of hypoxia and low temperature. The chapter concludes with a discussion of metabolic depression as an intrinsic metabolic mechanism that extends energy reserves when environmental conditions preclude activity.

This chapter details efforts by New Bedford's public officials to confront the challenges presented by the Civil War on fiscal management and municipal governance. It examines community debates over wartime costs, maintaining public services, and planning the city's postwar future. New Bedford's local officials coordinated with agents of state and national governments to meet unprecedented military expenses such as bounties. Despite the pressures of an uncertain war and an economic downturn, the city avoided large deficits by cutting costs in key areas such as public schools and collecting taxes with great efficiency. The issue of supplying New Bedford with fresh water, and its huge price tag, divided business and political leaders during a wartime referendum in 1864. Another municipal responsibility impacted directly by the Civil War was New Bedford's generous program of welfare administered by the Overseers of the Poor.

Escalating human demands for fresh water are jeopardising the intrinsic biodiversity values, ecological health, and vital ecosystem services of the rivers, wetlands, and estuaries upon which millions of humans depend for water, food, and secure housing, as well as for quality of life, health, and prosperity. Climate change exacerbates these pressures by affecting the global water cycle, freshwater availability, and the ecological health of aquatic ecosystems. Restoration of biodiversity, ecosystem function, and resiliency is a global imperative for water managers, scientists, and civil society. This chapter introduces the main argument of the book, which is that to sustain freshwater and estuarine ecosystems the natural volumes and variability patterns of standing and flowing water must be maintained through provision of “environmental flows.”

The Rankine closed cycle is a process in which beat is used to evaporate a fluid at constant pressure in a “boiler” or evaporator, from which the vapor enters a piston engine or turbine and expands doing work. The vapor exhaust then enters a vessel where heat is transferred from the vapor to a cooling fluid, causing the vapor to condense to a liquid, which is pumped back to the evaporator to complete the cycle. A layout of the plantship shown in Fig. 1-2. The basic cycle comprises four steps, as shown in the pressure-volume (p—V) diagram of Fig. 4-1. 1. Starting at point a, heat is added to the working fluid in the boiler until the temperature reaches the boiling point at the design pressure, represented by point b. 2. With further heat addition, the liquid vaporizes at constant temperature and pressure, increasing in volume to point c. 3. The high-pressure vapor enters the piston or turbine and expands adiabatically to point d. 4. The low-pressure vapor enters the condenser and, with heat removal at constant pressure, is cooled and liquefied, returning to its original volume at point a. The work done by the cycle is the area enclosed by the points a,b,c,d,a. This is equal to Hc–Hd, where H is the enthalpy of the fluid at the indicated point. The heat transferred in the process is Hc–Ha Thus the efficiency, defined as the ratio of work to heat used, is: . . . efficiency(η)=Hc–Hd/Hc–Ha (4.1.1) . . . Carnot showed that if the heat-engine cycle was conducted so that equilibrium conditions were maintained in the process, that the efficiency was determined solely by the ratio of the temperatures of the working fluid in the evaporator and the condenser. . . . η=TE–Tc/TE (4.1.2) . . . The maximum Carnot efficiency can be attained only for a cycle in which thermal equilibrium exists in each phase of the process; however, for power to be generated a temperature difference must exist between the working fluid in the evaporator and the warm-water heat source, and between the working fluid in the condenser and the cold-water heat sink.

Systems engineering is a top-down approach to program management and systems procurement. It optimizes the development process by ensuring that the operational, technical, and cost goals (and limitations) of a total proposed system are understood before development begins. The requirements for the “forest” are determined before the features of the “trees” are specified. It makes a basic assumption that a team endeavor under single-system management will be established with authority to define development goals and assign subsystem programs and funding. It recognizes that each system requires a unique management structure that is based on the qualifications of the people and organizations available for the total endeavor. Systems engineering begins with an authoritative request or requirement for a system that would provide new capabilities or would reduce existing problems in a significant technical activity. After personnel and level of effort for a preliminary assessment of the need are identified, the initial effort then involves these steps: 1. A precise definition is prepared of the specific operational need for which the proposed system must provide a solution. For example, this book addresses the present national need for a new energy system that can provide a practical, timely, cost-effective, and nonpolluting alternative to petroleum-based fuels for transportation. The need arises from three factors: a. The perception that an alternative to dependence on petroleum fuels for transportation must be developed to avoid severe disruption of world economies in the early years of the twenty-first century; b. Evidence that combustion of fossil fuels is causing a significant increase in the carbon dioxide content of the atmosphere (if not reduced, this could eventually produce a “greenhouse effect,” leading to large-scale changes in climate and an increase in sea level, with severe economic consequences); and c. The belief that solar energy can be used via OTEC to supply nonpolluting fuel in sufficient quantity, at low enough cost, and in time to become a practical alternative to dwindling or unavailable petroleum supplies. Failure to define the system need with sufficient clarity is a root cause of most system development difficulties.