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 rally 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.
Based on the given materials, the reading as well as the listening discusses whether an ancient weapon called "Burning mirror" existed or not. According to the lecturer the arguments provided by the reading are not convincing and challenges these ideas which raise a doubt on existance of the weapon.
Initially, the reading states that the weapon would have been too large and too exact so Greeks could not have made it since they where not technologicaly advanced enough. However the lecturer proclaims that they did not need a single mirror because a dozen of smaller mirrors would have been as effective as a sole big mirror. The greek mathemations new about this idea and Greeks were capable of making several small but exact mirrors so as a result they could make the weapon.
Second, The writer points out that the weapon was not practical since it would have taken a long time to burn a ship and eloborates on this by mentioning an experiment. Yet again, the speaker opposes this idea and points out a faulty assumption for the experiment. She points out the experiment was done on only wood while a ship is made of othere matterials too. She names a chemical which is used to seal the sip and makes it water proof. This chemical is highly flamabe and within secind it burns so it can cause the ship too catch fire and concludes that the weapon is effective.
Finally, the last poin of contention between the reading and listening passages is flamig arrows which could have been effective and eliminates the need for a new weapon. On the other hand, The speaker mentions that romans were familiar with these arrows and could prepare themselves for encountering with them so they would not have the same affect as burning mirror. She mentions that roman could see the arrows coming but the effect of the burning was invisible to them since suddenly a fire starts without knowing where did it came from and the might have thought it is magical.
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- TPO-25 - Independent Writing Task 3
Grammar and spelling errors:
Line 5, column 131, Rule ID: THEY_WHERE[1]
Message: Did you mean 'were', the simple past of "to be"?
Suggestion: were
...reeks could not have made it since they where not technologicaly advanced enough. How...
^^^^^
Line 5, column 173, Rule ID: SENT_START_CONJUNCTIVE_LINKING_ADVERB_COMMA[1]
Message: Did you forget a comma after a conjunctive/linking adverb?
Suggestion: However,
...ere not technologicaly advanced enough. However the lecturer proclaims that they did no...
^^^^^^^
Line 9, column 429, Rule ID: EN_COMPOUNDS
Message: This word is normally spelled as one.
Suggestion: waterproof
...ch is used to seal the sip and makes it water proof. This chemical is highly flamabe and wi...
^^^^^^^^^^^
Line 9, column 526, Rule ID: TOO_TO[1]
Message: Did you mean 'to catch'?
Suggestion: to catch
...ecind it burns so it can cause the ship too catch fire and concludes that the weapon is e...
^^^^^^^^^
Transition Words or Phrases used:
but, finally, however, second, so, well, while, as a result, as well as, on the other hand
Attributes: Values AverageValues Percentages(Values/AverageValues)% => Comments
Performance on Part of Speech:
To be verbs : 15.0 10.4613686534 143% => OK
Auxiliary verbs: 13.0 5.04856512141 257% => Less auxiliary verb wanted.
Conjunction : 16.0 7.30242825607 219% => Less conjunction wanted
Relative clauses : 11.0 12.0772626932 91% => OK
Pronoun: 29.0 22.412803532 129% => Less pronouns wanted
Preposition: 30.0 30.3222958057 99% => OK
Nominalization: 6.0 5.01324503311 120% => OK
Performance on vocabulary words:
No of characters: 1635.0 1373.03311258 119% => OK
No of words: 341.0 270.72406181 126% => OK
Chars per words: 4.79472140762 5.08290768461 94% => OK
Fourth root words length: 4.29722995808 4.04702891845 106% => OK
Word Length SD: 2.46577173954 2.5805825403 96% => OK
Unique words: 174.0 145.348785872 120% => OK
Unique words percentage: 0.510263929619 0.540411800872 94% => More unique words wanted or less content wanted.
syllable_count: 504.9 419.366225166 120% => OK
avg_syllables_per_word: 1.5 1.55342163355 97% => OK
A sentence (or a clause, phrase) starts by:
Pronoun: 4.0 3.25607064018 123% => OK
Article: 7.0 8.23620309051 85% => OK
Subordination: 0.0 1.25165562914 0% => More adverbial clause wanted.
Conjunction: 1.0 1.51434878587 66% => OK
Preposition: 2.0 2.5761589404 78% => OK
Performance on sentences:
How many sentences: 13.0 13.0662251656 99% => OK
Sentence length: 26.0 21.2450331126 122% => The Avg. Sentence Length is relatively long.
Sentence length SD: 37.915976867 49.2860985944 77% => OK
Chars per sentence: 125.769230769 110.228320801 114% => OK
Words per sentence: 26.2307692308 21.698381199 121% => OK
Discourse Markers: 6.92307692308 7.06452816374 98% => 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 : 8.0 4.45695364238 179% => OK
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: 0.158142959152 0.272083759551 58% => OK
Sentence topic coherence: 0.058424120053 0.0996497079465 59% => OK
Sentence topic coherence SD: 0.0606907224237 0.0662205650399 92% => OK
Paragraph topic coherence: 0.104286551127 0.162205337803 64% => OK
Paragraph topic coherence SD: 0.0538522684405 0.0443174109184 122% => OK
Essay readability:
automated_readability_index: 14.2 13.3589403974 106% => OK
flesch_reading_ease: 53.55 53.8541721854 99% => OK
smog_index: 3.1 5.55761589404 56% => Smog_index is low.
flesch_kincaid_grade: 12.3 11.0289183223 112% => OK
coleman_liau_index: 10.8 12.2367328918 88% => OK
dale_chall_readability_score: 8.35 8.42419426049 99% => OK
difficult_words: 74.0 63.6247240618 116% => OK
linsear_write_formula: 13.5 10.7273730684 126% => OK
gunning_fog: 12.4 10.498013245 118% => OK
text_standard: 14.0 11.2008830022 125% => OK
What are above readability scores?
---------------------
Write the essay in 20 minutes.
Rates: 81.6666666667 out of 100
Scores by essay e-grader: 24.5 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.