▶ Your Answer :
The
reading passages contends several theories to explain the origin of Iron Age
forts built with vitrified stones in Scotland. However, the speaker brings up
several ideas to contradict all the theories.
First,
the speaker disputes the theory about signal fires. The author of reading
passage suggests that fires used to communicate with other communities caused
vitrification of surfaces of stones. However, the speaker points that the
places used for fires are only one or two places. In means that entire walls
cannot be vitrified by fires. This fact cast doubt on the argument.
Second,
the theory related to lightning is also refuted by the speaker. The author
argues that repeated strikes of lightning transformed rock into a vitrified
state. On the other hand, according to the speaker, it is implausible that the
lightning occurs in the same place repeatedly. The crack, which is suggested as
an evidence of the lightning theory may be also just caused by weathering over
long ages. This refutes the theory about lightning effectively.
Finally,
the speaker points that the theory about volcanic rocks is simply wrong.
According to the speaker, people used local materials for construction, but
there is no evidence for volcanic activities at the region. Furthermore, it is
not plausible that the people carried the heavy volcanic rocks from other
regions far from them. This contradicts the theory related to volcanic rocks.
All
in all, the lecturer asserts that all the theories which the author suggested
as the origin of forts in Scotland are problematic. |