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.
the reading claims that the story of burning mirror as a defensive device in ancient Greek is not true and they never used from that in their war and bring three reasons to prove this. However, the lecturer finds all the ideas dubious and presents some evidence to refute them all.
the author argues that ancient Greek was not developed in building such a tremendous copper sheet for mirror and it was impossible for them. Conversely, the lecturer brings up the idea that there is an experiments that show a small polished copper may do the same job in a good way and Greek mathematicians were excellent enough to accomplish it perfectly.
furthermore, the reading passage holds the view that burning mirror would have taken a long time to set a wooden ship on fire and the enemy would not be stupid to stay still for ten minutes. On the contrary, the professor underlines the fact that there was an especial material that have been used that called pitch and got the fire so quickly even the ship was moving so they burnt the pitch first then the ship by burning mirror.
Finally, the reading asserts that Greek ancient had a flexible and more effective weapon that called flaming arrows. Thus building an other one that was not more better than flaming arrows was not necessary for them. In contrast, the speaker dismisses this issue due to the fact that roman soldiers were familiar with that old weapons and knew how to protect the ship from that device but about burning mirror they could not see it and predict where the fire will come down so it is more effective than flaming arrows.
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Grammar and spelling errors:
Line 1, column 1, Rule ID: UPPERCASE_SENTENCE_START
Message: This sentence does not start with an uppercase letter
Suggestion: The
the reading claims that the story of burnin...
^^^
Line 1, column 146, Rule ID: WHITESPACE_RULE
Message: Possible typo: you repeated a whitespace
Suggestion:
...d they never used from that in their war and bring three reasons to prove this. H...
^^
Line 2, column 1, Rule ID: UPPERCASE_SENTENCE_START
Message: This sentence does not start with an uppercase letter
Suggestion: The
...ents some evidence to refute them all. the author argues that ancient Greek was no...
^^^
Line 2, column 190, Rule ID: THERE_S_MANY[4]
Message: Did you mean 'there are an experiments'?
Suggestion: there are an experiments
...y, the lecturer brings up the idea that there is an experiments that show a small polished copper may d...
^^^^^^^^^^^^^^^^^^^^^^^
Line 2, column 199, Rule ID: A_PLURAL[1]
Message: Don't use indefinite articles with plural words. Did you mean 'an experiment' or simply 'experiments'?
Suggestion: an experiment; experiments
...cturer brings up the idea that there is an experiments that show a small polished copper may d...
^^^^^^^^^^^^^^
Line 3, column 1, Rule ID: UPPERCASE_SENTENCE_START
Message: This sentence does not start with an uppercase letter
Suggestion: Furthermore
...ent enough to accomplish it perfectly. furthermore, the reading passage holds the view tha...
^^^^^^^^^^^
Line 4, column 131, Rule ID: AN_OTHER[1]
Message: Did you mean 'another'? This word sequence is usually spelled together.
Suggestion: another
...at called flaming arrows. Thus building an other one that was not more better than flami...
^^^^^^^^
Line 4, column 157, Rule ID: MOST_COMPARATIVE[2]
Message: Use only 'better' (without 'more') when you use the comparative.
Suggestion: better
...Thus building an other one that was not more better than flaming arrows was not necessary f...
^^^^^^^^^^^
Transition Words or Phrases used:
but, conversely, finally, first, furthermore, however, may, so, still, then, thus, in contrast, on the contrary
Attributes: Values AverageValues Percentages(Values/AverageValues)% => Comments
Performance on Part of Speech:
To be verbs : 13.0 10.4613686534 124% => OK
Auxiliary verbs: 5.0 5.04856512141 99% => OK
Conjunction : 11.0 7.30242825607 151% => OK
Relative clauses : 16.0 12.0772626932 132% => OK
Pronoun: 28.0 22.412803532 125% => Less pronouns wanted
Preposition: 22.0 30.3222958057 73% => OK
Nominalization: 1.0 5.01324503311 20% => More nominalizations (nouns with a suffix like: tion ment ence ance) wanted.
Performance on vocabulary words:
No of characters: 1313.0 1373.03311258 96% => OK
No of words: 283.0 270.72406181 105% => OK
Chars per words: 4.63957597173 5.08290768461 91% => OK
Fourth root words length: 4.10153676581 4.04702891845 101% => OK
Word Length SD: 2.24850515895 2.5805825403 87% => OK
Unique words: 158.0 145.348785872 109% => OK
Unique words percentage: 0.558303886926 0.540411800872 103% => OK
syllable_count: 396.9 419.366225166 95% => OK
avg_syllables_per_word: 1.4 1.55342163355 90% => OK
A sentence (or a clause, phrase) starts by:
Pronoun: 0.0 3.25607064018 0% => OK
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: 9.0 13.0662251656 69% => Need more sentences. Double check the format of sentences, make sure there is a space between two sentences, or have enough periods. And also check the lengths of sentences, maybe they are too long.
Sentence length: 31.0 21.2450331126 146% => The Avg. Sentence Length is relatively long.
Sentence length SD: 65.6112757548 49.2860985944 133% => OK
Chars per sentence: 145.888888889 110.228320801 132% => OK
Words per sentence: 31.4444444444 21.698381199 145% => OK
Discourse Markers: 12.3333333333 7.06452816374 175% => OK
Paragraphs: 4.0 4.09492273731 98% => OK
Language errors: 8.0 4.19205298013 191% => 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: 0.0 4.27373068433 0% => More facts, knowledge or examples wanted.
What are sentences with positive/Negative/neutral sentiment?
Coherence and Cohesion:
Essay topic to essay body coherence: 0.166042060666 0.272083759551 61% => OK
Sentence topic coherence: 0.0701021622532 0.0996497079465 70% => OK
Sentence topic coherence SD: 0.0370572791888 0.0662205650399 56% => OK
Paragraph topic coherence: 0.0996367214679 0.162205337803 61% => OK
Paragraph topic coherence SD: 0.0272055046195 0.0443174109184 61% => OK
Essay readability:
automated_readability_index: 16.1 13.3589403974 121% => OK
flesch_reading_ease: 56.93 53.8541721854 106% => OK
smog_index: 3.1 5.55761589404 56% => Smog_index is low.
flesch_kincaid_grade: 13.0 11.0289183223 118% => OK
coleman_liau_index: 10.22 12.2367328918 84% => OK
dale_chall_readability_score: 7.85 8.42419426049 93% => OK
difficult_words: 48.0 63.6247240618 75% => More difficult words wanted.
linsear_write_formula: 13.5 10.7273730684 126% => OK
gunning_fog: 14.4 10.498013245 137% => OK
text_standard: 14.0 11.2008830022 125% => OK
What are above readability scores?
---------------------
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.