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 the lecture are both about burning mirrors a weapon of Greeks, which was used as a war weapon. The author of the reading believes that the concept of the burning mirror is a myth and such kind of weapon was never built by the Greeks. The lecturer challenges the statements made by the author. She is of the opinion that actually such kind of weapon existed.
First of all, the author suggests that to become a burning mirror it would be several meters wide. It is mentioned that the mirror would have to have a parabolic curve and such kind of technology did not exist in ancient Greek. This argument is challenged by the lecturer. She says that for making a wide mirror, there was no need of large copper sheet and ancient greek has small flat of copper sheet which could be connected to each other to make of large mirror. Furthermore, she argues that the ancient mathematician had the knowledge of parabola and thus it was possible for them to make such a kind of weapon.
Secondly, the writer contends that to set fire on the ship’s mirror needs a long time. He refers to an experiment which was conducted on a wooden object which was 30 meter away and took ten minutes to set fire. The lecturer, however, rebuts this by asserting that the wooden boats were not only made of wooden but also space between two wooden pieces were filled by pitch which was easily ignified in a sec. She elaborating on this by bringing up the point that this ignition of pitch helped to set fire on whether the ship was moving or not. So, it was an effective method for setting fire through a burning mirror.
Finally, the author posits that a burning mirror was not the substitution and improvement of Greek weapons which were generally used in war. Moreover, in the article, it is stated that there was another way to set fire on ships. So, there was no need for building such a weapon like a burning mirror. The lecturer, on the other hand, posits that the observer of the enemy ships observe the incoming flaming arrows and could make all cautious by signaling. She puts forth the idea that if burning mirror used in war they set fire suddenly that fire will spread before anyone took proper steps.
| Post date | Users | Rates | Link to Content |
|---|---|---|---|
| 2023-02-07 | Celia02200059 | 3 | view |
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Grammar and spelling errors:
Line 1, column 251, 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.
...f weapon was never built by the Greeks. The lecturer challenges the statements made...
^^^
Line 9, column 168, Rule ID: WHITESPACE_RULE
Message: Possible typo: you repeated a whitespace
Suggestion:
...s conducted on a wooden object which was 30 meter away and took ten minutes to se...
^^
Line 9, column 173, Rule ID: CD_NN[1]
Message: Possible agreement error. The noun 'meter' seems to be countable, so consider using: 'meters'.
Suggestion: meters
...ducted on a wooden object which was 30 meter away and took ten minutes to set fire. ...
^^^^^
Line 9, column 419, Rule ID: HE_VERB_AGR[1]
Message: The pronoun 'She' must be used with a third-person verb: 'elaborates'.
Suggestion: elaborates
...which was easily ignified in a sec. She elaborating on this by bringing up the point that t...
^^^^^^^^^^^
Transition Words or Phrases used:
actually, also, but, finally, first, furthermore, however, if, moreover, second, secondly, so, thus, kind of, first of all, on the other hand
Attributes: Values AverageValues Percentages(Values/AverageValues)% => Comments
Performance on Part of Speech:
To be verbs : 23.0 10.4613686534 220% => Less to be verbs wanted.
Auxiliary verbs: 7.0 5.04856512141 139% => OK
Conjunction : 10.0 7.30242825607 137% => OK
Relative clauses : 20.0 12.0772626932 166% => OK
Pronoun: 31.0 22.412803532 138% => Less pronouns wanted
Preposition: 51.0 30.3222958057 168% => OK
Nominalization: 5.0 5.01324503311 100% => OK
Performance on vocabulary words:
No of characters: 1823.0 1373.03311258 133% => OK
No of words: 400.0 270.72406181 148% => Less content wanted.
Chars per words: 4.5575 5.08290768461 90% => OK
Fourth root words length: 4.472135955 4.04702891845 111% => OK
Word Length SD: 2.30213895106 2.5805825403 89% => OK
Unique words: 193.0 145.348785872 133% => OK
Unique words percentage: 0.4825 0.540411800872 89% => More unique words wanted or less content wanted.
syllable_count: 560.7 419.366225166 134% => OK
avg_syllables_per_word: 1.4 1.55342163355 90% => OK
A sentence (or a clause, phrase) starts by:
Pronoun: 10.0 3.25607064018 307% => Less pronouns wanted as sentence beginning.
Article: 8.0 8.23620309051 97% => OK
Subordination: 0.0 1.25165562914 0% => More adverbial clause wanted.
Conjunction: 0.0 1.51434878587 0% => OK
Preposition: 2.0 2.5761589404 78% => OK
Performance on sentences:
How many sentences: 19.0 13.0662251656 145% => OK
Sentence length: 21.0 21.2450331126 99% => OK
Sentence length SD: 42.0762399972 49.2860985944 85% => OK
Chars per sentence: 95.9473684211 110.228320801 87% => OK
Words per sentence: 21.0526315789 21.698381199 97% => OK
Discourse Markers: 7.42105263158 7.06452816374 105% => OK
Paragraphs: 4.0 4.09492273731 98% => OK
Language errors: 4.0 4.19205298013 95% => OK
Sentences with positive sentiment : 3.0 4.33554083885 69% => OK
Sentences with negative sentiment : 14.0 4.45695364238 314% => Less negative sentences wanted.
Sentences with neutral sentiment: 2.0 4.27373068433 47% => OK
What are sentences with positive/Negative/neutral sentiment?
Coherence and Cohesion:
Essay topic to essay body coherence: 0.136698539536 0.272083759551 50% => OK
Sentence topic coherence: 0.0496317318808 0.0996497079465 50% => OK
Sentence topic coherence SD: 0.0431393991656 0.0662205650399 65% => OK
Paragraph topic coherence: 0.0917597879331 0.162205337803 57% => OK
Paragraph topic coherence SD: 0.0318260416522 0.0443174109184 72% => OK
Essay readability:
automated_readability_index: 10.6 13.3589403974 79% => Automated_readability_index is low.
flesch_reading_ease: 67.08 53.8541721854 125% => OK
smog_index: 3.1 5.55761589404 56% => Smog_index is low.
flesch_kincaid_grade: 9.1 11.0289183223 83% => OK
coleman_liau_index: 9.17 12.2367328918 75% => OK
dale_chall_readability_score: 7.56 8.42419426049 90% => OK
difficult_words: 73.0 63.6247240618 115% => OK
linsear_write_formula: 7.5 10.7273730684 70% => OK
gunning_fog: 10.4 10.498013245 99% => 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: 71.6666666667 out of 100
Scores by essay e-grader: 21.5 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.