A little over 2,200 years ago, the Roman navy attacked 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 the Sun’s rays onto Roman ships, causing them to catch fire. However, we have several reasons to suspect that the story of the burning mirror is just a myth and the Greeks of Syracuse never really built such a device.
First, the ancient Greeks were not technologically advanced enough to make such a device. A mirror that would focus sunlight with sufficient intensity to set ships on fire would have to be several meters wide. Moreover, the mirror would have to have a very precise parabolic curvature (a curvature derived from a geometric shape known as the parabola). The technology for manufacturing a large sheet of copper with such specifications did not exist in the ancient world.
Second, the burning mirror would have taken a long time to set the ships on fire. In an experiment conducted to determine whether a burning mirror was feasible, a device concentrating the Sun’s rays on a wooden object 30 meters away took ten minutes to set the object on fire; and during that time, the object had to be unmoving. It is unlikely that Roman ships stayed perfectly still for that much time. Such a weapon would therefore have been very impractical and ineffective.
Third, a burning mirror does not seem like an improvement on a weapon that the Greeks already had: flaming arrows. Shooting at an enemy’s ships with flaming arrows was a common way of setting the ships on fire. The burning mirror and flaming arrows would have been effective at about the same distance. So the Greeks had no reason to build a weapon like a burning mirror.
The reading and lecture are both about the burning mirror. The author of the reading believes that there was no existence of a burning mirror in ancient Greek. The lecturer challenges the statements made by the author. She is of the opinion that the existence of the burning mirror is real and there were several reasons for its existence.
First of all, the author claims that Greeks were not technologically advanced to make such a kind of device. In addition, it mentioned that the mirror would have to be several meters wide and would have the parabolic shape and that was impossible for the ancient world. The lecturer expresses a contrast to the argument. She says that in the ancient world there exist small flat copper sheets that could be combined together to make a wide copper sheet. Furthermore, she claims that ancient mathematicians had the knowledge of parabola.
Secondly, the writer contends that it took a long time to set fire on ships and to set fire ships must be still perfectly. The article notes about an experiment on a wooden ship 30 meters away took 10 minutes to set fire by the burning mirror. the lecturer, however, rebuts this by asserting that wooden ships were not only made of wood but also the gap among wood filled with pitch. She elaborating on this by bringing up the point that pitch takes less than a second to set fire and rapidly spread whether the object is moving or still.
Finally, the author posits that Greeks already had the flamming arow which could set fire easily. Moreover, in the article, it is stated that the burning mirror and flaming arrows would have been the same effectiveness from the viewpoint of distance. On the other hand, the lecturer posits that burning mirrors was more effective than flaming arrows. She puts forth on the idea that without being noticed significantly the burning mirror could set fire on the enemy ships and could spread fear.
| Post date | Users | Rates | Link to Content |
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Grammar and spelling errors:
Line 1, column 161, Rule ID: ENGLISH_WORD_REPEAT_BEGINNING_RULE
Message: Three successive sentences begin with the same word. Reword the sentence or use a thesaurus to find a synonym.
...e of a burning mirror in ancient Greek. The lecturer challenges the statements made...
^^^
Line 9, column 245, Rule ID: UPPERCASE_SENTENCE_START
Message: This sentence does not start with an uppercase letter
Suggestion: The
...utes to set fire by the burning mirror. the lecturer, however, rebuts this by asser...
^^^
Line 9, column 389, Rule ID: HE_VERB_AGR[1]
Message: The pronoun 'She' must be used with a third-person verb: 'elaborates'.
Suggestion: elaborates
...e gap among wood filled with pitch. She elaborating on this by bringing up the point that p...
^^^^^^^^^^^
Transition Words or Phrases used:
also, but, finally, first, furthermore, however, if, moreover, second, secondly, so, still, in addition, kind of, first of all, on the other hand
Attributes: Values AverageValues Percentages(Values/AverageValues)% => Comments
Performance on Part of Speech:
To be verbs : 16.0 10.4613686534 153% => OK
Auxiliary verbs: 8.0 5.04856512141 158% => OK
Conjunction : 10.0 7.30242825607 137% => OK
Relative clauses : 16.0 12.0772626932 132% => OK
Pronoun: 26.0 22.412803532 116% => OK
Preposition: 39.0 30.3222958057 129% => OK
Nominalization: 7.0 5.01324503311 140% => OK
Performance on vocabulary words:
No of characters: 1597.0 1373.03311258 116% => OK
No of words: 332.0 270.72406181 123% => OK
Chars per words: 4.81024096386 5.08290768461 95% => OK
Fourth root words length: 4.2685907696 4.04702891845 105% => OK
Word Length SD: 2.4230556432 2.5805825403 94% => OK
Unique words: 167.0 145.348785872 115% => OK
Unique words percentage: 0.503012048193 0.540411800872 93% => More unique words wanted or less content wanted.
syllable_count: 484.2 419.366225166 115% => OK
avg_syllables_per_word: 1.5 1.55342163355 97% => OK
A sentence (or a clause, phrase) starts by:
Pronoun: 7.0 3.25607064018 215% => Less pronouns wanted as sentence beginning.
Article: 10.0 8.23620309051 121% => OK
Subordination: 0.0 1.25165562914 0% => More adverbial clause wanted.
Conjunction: 0.0 1.51434878587 0% => OK
Preposition: 3.0 2.5761589404 116% => OK
Performance on sentences:
How many sentences: 17.0 13.0662251656 130% => OK
Sentence length: 19.0 21.2450331126 89% => OK
Sentence length SD: 33.5279669451 49.2860985944 68% => OK
Chars per sentence: 93.9411764706 110.228320801 85% => OK
Words per sentence: 19.5294117647 21.698381199 90% => OK
Discourse Markers: 8.52941176471 7.06452816374 121% => OK
Paragraphs: 4.0 4.09492273731 98% => OK
Language errors: 3.0 4.19205298013 72% => OK
Sentences with positive sentiment : 3.0 4.33554083885 69% => OK
Sentences with negative sentiment : 6.0 4.45695364238 135% => OK
Sentences with neutral sentiment: 8.0 4.27373068433 187% => OK
What are sentences with positive/Negative/neutral sentiment?
Coherence and Cohesion:
Essay topic to essay body coherence: 0.117020903369 0.272083759551 43% => OK
Sentence topic coherence: 0.0425726811852 0.0996497079465 43% => OK
Sentence topic coherence SD: 0.0364145726462 0.0662205650399 55% => OK
Paragraph topic coherence: 0.0775620433408 0.162205337803 48% => OK
Paragraph topic coherence SD: 0.0311735976168 0.0443174109184 70% => OK
Essay readability:
automated_readability_index: 11.0 13.3589403974 82% => Automated_readability_index is low.
flesch_reading_ease: 60.65 53.8541721854 113% => OK
smog_index: 3.1 5.55761589404 56% => Smog_index is low.
flesch_kincaid_grade: 9.5 11.0289183223 86% => OK
coleman_liau_index: 10.62 12.2367328918 87% => OK
dale_chall_readability_score: 7.67 8.42419426049 91% => OK
difficult_words: 65.0 63.6247240618 102% => OK
linsear_write_formula: 8.0 10.7273730684 75% => OK
gunning_fog: 9.6 10.498013245 91% => OK
text_standard: 8.0 11.2008830022 71% => OK
What are above readability scores?
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Write the essay in 20 minutes.
Rates: 75.0 out of 100
Scores by essay e-grader: 22.5 Out of 30
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Note: the e-grader does NOT examine the meaning of words and ideas. VIP users will receive further evaluations by advanced module of e-grader and human graders.