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81.
82.
Abstract

Abraham Lincoln presented a lecture in 1858–1859 on the process of “Discoveries and Invention.” In this lecture he discusses man's desire to improve his condition and the use of technology to that end. The process of discovery and invention allows man to develop that technology and alleviate his state. Education, especially literacy, allows knowledge to be passed down through time, facilitating yet further improvement. Yet, Lincoln warns that human nature can also become raw material, as seen in the institution of slavery. In light of Lincoln's more commonly known natural rights argument against slavery, this warning about human nature takes on greater significance. Coupled with an address on agriculture from 1859, Lincoln's lecture on discovery and invention attempts to illustrate the liberating power of invention and education while reminding us of the limits posed by man's natural equality.  相似文献   
83.

Along the coast of Norway we find a family of closely‐related boats. The Nordlands boat is one of them, and in many respects it is the most modern. The plan for the shape of these boats is typically coded into figures. Thus the “secret” of the boat's structure is a sort of “number code”. The question addressed here is: to what extent can the shape of the hull in Viking ships be expressed as a number code similar to that of the 19th‐century west‐coast boats of Norway. The principles behind the methods used to explore this question will be illustrated by three basic concepts, which will be treated separately below.  相似文献   
84.
California and Great Basin archaeologists have long discussed and debated the function of chipped stone crescents found in Terminal Pleistocene and Early Holocene sites in the Far West of North America. Because they are found over a vast area, in sites occupied over a period spanning at least 4,000 years (~12,000–8,000 cal BP), it may be that crescents were used for a variety of purposes. Here we focus on lunate crescents and their strong association with wetland localities (lakes, marshes, estuaries, and islands). We reconsider whether crescents could have been used as transverse projectile points to hunt waterfowl. We also assess the biogeographical legacies of migrating birds to propose that as many as four species of large anatids (tundra swan, greater white-fronted goose, snow goose, Ross’s goose) that now breed in the Canadian High Arctic once bred in the Great Basin and adjacent regions during the Late Pleistocene and Early Holocene. We propose that crescents were used primarily in the taking or processing of geese and swans, some of which may have bred and molted in what are now temperate latitudes. After the Laurentide ice sheet retreated, these four species established High Arctic breeding grounds and no longer bred in the Great Basin. In this scenario, the absence of some populations of molting geese and swans helps explain why crescents fell out of the archaeological record after ~8,000 cal. BP. When crescents were used, Native Americans in the Far West may have had access to millions of large waterfowl.  相似文献   
85.
Abstract

High-resolution NEXTMap digital surface models and aerial photographs are used to map suites of transverse ridges at Tarbat Ness and to the west of Elgin, along the margins of the Moray Firth in northeast Scotland. Based on their morphology, configuration and location, interpret these landforms as De Geer moraines which formed at or near former grounding line positions of the Moray Firth palaeo-ice stream. The Tarbat Ness De Geer moraines almost certainly formed at a marine margin. Reaching altitudes of 55 m above present OD, these landforms may provide one of the highest geomorphological indicators for former relative sea level in mainland Britain. Evidence from surrounding landforms and sediments suggest that the ridges formed between c. 15 000–18 000 cal yrs BP, indicating that a significant fall in relative sea level may have taken place prior to an ice margin re-advance in the Moray Firth, known as the Ardersier Oscillation.  相似文献   
86.
While it has been argued that conventional methodological resources are incapable of effectively representing ‘everyday social practice’ (see Latham 2003 Latham, A. 2003. Research, performance, and doing human geography: Some reflections on the diary-photograph, diary-interview method. Environment and Planning A, 35: 19932017. [Crossref], [Web of Science ®] [Google Scholar], Environment and Planning A, 35, 1993), this paper posits that a consideration of the ‘where’ of methodology can go some way to taking social practices seriously. Drawing on research into young people's spatial practices, conventional interview techniques were adopted in a range of different sites: a classroom, a school store-cupboard, and in teenage ‘hang outs’. Through discussion of these emplaced techniques, the paper demonstrates the difference the where of method makes to research. It will argue that, if harnessed appropriately, emplaced methodology can enhance social science's capacity to access the range of intelligences that constitute everyday social practice.  相似文献   
87.
88.
Jon May  Paul Cloke  Sarah Johnsen 《对极》2005,37(4):703-730
In this paper we continue the task of fleshing out understandings of "actually existing neoliberalism". More specifically, drawing on the work of Tom Ling, we suggest that Peck and Tickell's recent distinction between periods of roll‐back/roll‐out neoliberalisation can usefully be supplemented by the identification of a second, more powerful moment of roll‐out neoliberalism—described by Ling in terms of the shift from a system of governance to one of "governmentality". Illustrating our argument with an analysis of changing central government responses to a crisis of street homelessness in 1990s Britain, however, we draw attention to the uneven and often contrary effects of recent government policy in this field. The paper therefore concludes with a warning of the need to temper a reading of the juggernaut of roll‐out neoliberalism with an awareness of the incomplete and plain "messy" character of actually existing neoliberalisation.  相似文献   
89.
Urban evolution in the USA   总被引:17,自引:0,他引:17  
On a sustained basis, cities are of non-uniform relative sizes.This paper addresses three basic issues which arise from thissimple observation by examining the size distribution of UScities over the period 1900–1990. First, we explore thereasons why there is a wide distribution of city sizes. Second,we characterize the evolution of the size distribution of cities,documenting growth in sizes and numbers of cities. We ask whetherthe relative size distribution of cities has remained stableover time, or if it has displayed, instead, a tendency to collapse,flatten, or otherwise change its shape. We also examine evidenceon whether the size distribution obeys Zipf's Law. Third, weexamine the degree and determinants of mobility of individualcities within this distribution, asking to what extent citiesare moving up and down in the distribution and how this movementis influenced by cities' geographic characteristics. We usea newly constructed data with consistent metropolitan area definitionsover this century, discussing the issues and linking our resultsto the relevant literature.  相似文献   
90.
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