A little over 2,200 years ago, the Roman navy attached the Greek port city of Syracuse. According to some ancient historians, the Greeks defended themselves with an ingenious weapon called a “burning mirror”: a polished copper surface curved to focus

In this set of materials, both the reading and the lecture discuss whether " The story of burning mirror was real or not". Whereas, the reading suggests that this event didn't exist, the listener disregards the article and posits some reasons that she thinks overweight those in the article.

First, the article says that Greeks didn't have a suitable technology to develop such a machine with this description. Notwithstanding, the listener posits that the Roman didn't use a single sheet of copper and instead they used thousands of mirror arranged in a parabolic form. In other words, using those amount of mirrors they could evoke the effect of burning.

Second, in the article the author explains that the time used to produce fire on their enemies was impractical because according to some experiments they would have to wait a long time before producing a fire on their enemies with the burning mirror. The listener disagrees with this idea and suggests that in the experiment mentioned in the article; they only focused on wood as reference to assess the burning mirror. Nevertheless, they also used other pitch that is a very flammable material used to join wood.

Third, the reading says that Greeks already had a weapon similar to this one called the flaming arrows, thus the burning mirrors were not an improvement of the weapon mentioned. On the other hand, the listener says that the burning mirror possessed characteristics and advantages that the flaming arrows didn't have; like a more accurate and effective usage.

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using those amount of mirrors they could evoke the effect of burning.
by using those amount of mirrors, they could evoke the effect of burning.

they also used other pitch that is a very flammable material used to join wood.
they also used another pitch that is a very flammable material used to join wood.

Attribute Value Ideal
Score: 24 in 30
Category: Good Excellent
No. of Grammatical Errors: 2 2
No. of Spelling Errors: 0 2
No. of Sentences: 11 12
No. of Words: 257 250
No. of Characters: 1247 1200
No. of Different Words: 131 150
Fourth Root of Number of Words: 4.004 4.2
Average Word Length: 4.852 4.6
Word Length SD: 2.539 2.4
No. of Words greater than 5 chars: 91 80
No. of Words greater than 6 chars: 68 60
No. of Words greater than 7 chars: 35 40
No. of Words greater than 8 chars: 24 20
Use of Passive Voice (%): 0 0
Avg. Sentence Length: 23.364 21.0
Sentence Length SD: 9.335 7.5
Use of Discourse Markers (%): 0.636 0.12
Sentence-Text Coherence: 0.377 0.35
Sentence-Para Coherence: 0.617 0.50
Sentence-Sentence Coherence: 0.078 0.07
Number of Paragraphs: 4 4