▶ Your Answer :
The lecturer argues that none of the theories which explain the vitrification of the stones of the Scottish forts are not confirmed yet. While the reading passage introduces three theories regarding the origin of the vitrification, the lecturer counters each of the theories with his grounds.
First, the lecturer asserts that the vitrification cannot be caused by signal fires. Signal fires were used only in one or two places in a fort and the places were not changed. As a result, if the vitrification was caused by single fires, the vitrification should be found in a few areas of a fort. However the vitrification is found on the entire upper surface of the forts. This casts doubt on the reading passage’s claim that there is a chance that the vitrification was attributed to signal fires.
On top of that, the lecturer claims that the vitrification is not related with lightning. For a rock to get vitrified by lightning, the rock should have gotten several lightning strikes over and over again. However, it is almost impossible. In addition, there are some rocks which is almost 1m long and vitrified; It would be hardly made with lightning. The uneven appearance of the walls can be explained with its poor condition over a long period of time. This also refutes the reading passage’s claim that the vitrification of the stones were made by lightnings.
Finally, the lecturer contends that no evidence shows that there happened volcanic activity near the forts. According to the reading passage’s theory, people should have transported heavy volcanic material from a long distance; This is nonsense however. The lecturer explains the ancient Scottish should have used some local stones to build the forts. This counters the reading passage’s claim that the vitrification process might have happened before the construction of the forts. |