▶ Your Answer :
The
reading passage and the lecture are both about the reason for vitrification of
the forts in Scotland. Whereas the reading passage says that there are mainly 3
ways to explain the origin of the vitrified forts – signal fires, lightning
and volcanic rocks, the lecturer casts doubts on the authors’ opinions for
three reasons.
First of all, according to the reading,
vitrification might be caused by signal fires. Because signal fires along the
walls of the forts were used for communication with other communities, the
continual heat from the fire melted the rock over time. The lecturer, on the
other hand, points out that the signal fires were placed only 1 or 2 places
which were very small spots compared to the size of the whole fort, it is
impossible for signal fires to melt the entire walls.
Second, the author states that lightning
is another strong assumption for how the rocks of the forts were vitrified. A
single lightning strike is enough to transform the hard rocks to glass-like material,
and it also explains well why the rocks were broken in large chunks. However,
the lecturer argues that dozens of lightning were required to melt the entire
forts. She also says that the forts were damaged in pieces, not because of the
lightning, but because they are old.
Lastly, the author demonstrates that the forts
might be built with volcanic rocks which were the melting rocks by lava from the volcanic eruption. The lecturer does not agree with this point of view by
explaining that there are not volcanic activities in the region where the forts
are. Because people at that time used local materials for the construction, it
is not plausible that they moved heavy materials like volcanic rocks from
another region.
In conclusion, the lecturer effectively
challenges 3 possible reasons for vitrified rocks of the forts in the reading
passages. |