As you know, Ned, the importance--or lack thereof--of blue glass
beads to African Americans is being debated at present. We know, of
course, the traditional importance of them to Native Americans in the
16th and 17th centuries. As to house corners, I haven't heard that
one; however, when I excavated the Bermuda Hundred store we uncovered
a pier-built addition on the rear of the ca. 1800 stone-and-brick
building. The addition was built about 1850 (probably when William
Johnson became the merchant for BH--remember him? The failed
Forty-niner?--and there were three or four port wine bottles laid
very ceremoniously into the elbow of the northeast conrner brick
pier. This may have been a kind of dedication ceremonial offering (as
in the laying of a cornerstone), but I doubt it had anything to do
with superstitions about corners.
 
Dan