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The whole subject of forests, especially forests in the Middle Ages, is overlaid with a great deal of romanticism. The picture of a heavily-wooded England with primeval forests dotted here and there with villages connected by meandering tracks to relieve their isolation is fixed. Only a handful of Robin Hood bands lived within the depths of the forest itself. The present concern for man's destruction of his environment has caused this idyllic picture to be contrasted with the denuded landscape of large areas today, and the pathetic remnants of Sherwood Forest can be used as a cautionary lesson on industrialization since the eighteenth century. In fact, that lesson needs to be extended backward in time and the picture of the untouched medieval forest abandoned, for the reality was that men in the twelfth and thirteenth centuries made heavy use of the forests and encroached upon them just as man had done since he first came to the island or, more emphatically, since the Anglo-Saxon invaders began to make drastic changes in forested areas by their farming practices. However, after the Norman Conquest, the policies adopted for the royal forests did serve as some protection for the trees, even though the Norman kings no more had this as their purpose than had their predecessors. The thesis of this article is that the medieval English kings from the Normans on were conservationists in spite of themselves, even in the face of continuous demands from their own barons for disafforestment. Royal forest regulations enforced within the extensive areas under forest law protected the trees from complete destruction and slowed the inevitable encroachment of field upon forest.
We have established a correlation between localized states responsible for mid-gap optical emission and film mobility of GaN grown under different nitrogen conditions. By imposing a deflector voltage at the tip of the plasma source, we varied the ion/neutral flux ratio to determine how N ions affect mid-gap luminescence and electrical mobility. Low energy electron-excited nanometer scale luminescence (LEEN) spectroscopy in ultrahigh vacuum (UHV) showed mid-gap emission intensities in the bulk that decreased in the ratio, 50 : 1.3 : 1 with increasing deflector voltage. Hall measurements indicated over a factor of two increase in mobility, and a factor of 8 decrease in residual charge density with increasing deflector voltage. The correlation of optical and electrical properties with a reduction in N ion flux suggests the primary role of native defects, such as N or Ga vacancies, in the mid-gap emissions.