y #$Equator))</font></p>
                   
      <p>The GeoAgent is able to find bindings for the third clause by using
its own knowledge of the geography domain: </p>
             
      <ul>
        <li>Britain is in Europe.</li>
        <li>Europe is in the northern hemisphere.</li>
        <li>The northern hemisphere is north of the equator.</li>
        <li>If region A is part of region B, and region B is north of region
C, then region A is north of region C.</li>
        <li>Therefore, Britain is no