DOI Page / Citation link:
https://doi.org/10.11588/diglit.15#0096
86 THE GREAT PYRAMID.
when, in reality, they were in some lower latitude,
for the pole of the heavens rises higher and higher
above the horizon as we pass to higher and higher
latitudes. Thus they would set their station some-
what to the south of latitude 30o, instead of to the
north, as when they were supposed to have used
the shadow method. Here again we can find how
far they would set it south of that latitude. Using
the Greenwich refraction table (which is the same
as Bessel's), we find that they would have made a
much greater error than when using the other
method, simply because they would be observing a
body at an elevation of about thirty degrees only,
whereas in taking the sun's mid-day altitude in
spring or autumn, they would be observing a body
at twice as great an elevation. The error would
be, in fact, in this case, about 1 mile 1,51.2 yards.
It seems not at all unlikely that astronomers,
so skilful and ingenious as the builders of the
pyramid manifestly were, would have employed
both methods. In that case they would certainly
have obtained widely discrepant results, rough as
their means and methods must unquestionably
have been, compared with modern instruments and
methods. The exact determination from the
shadow plan would have set them 1,125 yards to
the north of the true latitude ; while the exact
when, in reality, they were in some lower latitude,
for the pole of the heavens rises higher and higher
above the horizon as we pass to higher and higher
latitudes. Thus they would set their station some-
what to the south of latitude 30o, instead of to the
north, as when they were supposed to have used
the shadow method. Here again we can find how
far they would set it south of that latitude. Using
the Greenwich refraction table (which is the same
as Bessel's), we find that they would have made a
much greater error than when using the other
method, simply because they would be observing a
body at an elevation of about thirty degrees only,
whereas in taking the sun's mid-day altitude in
spring or autumn, they would be observing a body
at twice as great an elevation. The error would
be, in fact, in this case, about 1 mile 1,51.2 yards.
It seems not at all unlikely that astronomers,
so skilful and ingenious as the builders of the
pyramid manifestly were, would have employed
both methods. In that case they would certainly
have obtained widely discrepant results, rough as
their means and methods must unquestionably
have been, compared with modern instruments and
methods. The exact determination from the
shadow plan would have set them 1,125 yards to
the north of the true latitude ; while the exact