Paul McWilliams
TC 410
Assignment 1—Analysis and Revision of Technical Prose
The assignment is to find a technical piece of writing (a report of some sort) and to analyze it for purpose, persona, intended reader, tone, bias, and style. Report your findings below. Then, keeping these elements the same, rewrite a paragraph (around 300 words) to improve the style.
Turn in this sheet with your revision.
1. Its purpose?
This book is intended to serve as an individual study resource for US Navy Quartermasters (navigation specialists) to help them learn their job and prepare for advancement exams.
2. Its persona?
The persona is not explicitly apparent. The writers paint themselves as more experienced peers of the reader. In some cases they use the pronoun “we” and “ourselves” to collectively refer to the writer and to the reader. The writer’s voice is friendly but authoritative. It appears to sort of be the collective knowledge of the quartermasters that have gone before inviting the reader to learn.
3. Its intended reader?
The intended reader of this book is an enlisted person in the US Navy. He or she is treated, in the text, as a person who is enthusiastic and eager to learn their specialty but who does not have a lot of prior inside knowledge. The reader is referred to by the pronoun “you” often throughout the text. The reader is thought to be intelligent and capable of learning, but is only assumed to have a high-school education. For example, part of the introduction reads “As you will learn navigation is both an art and a science. Don’t be put off by the science end though, a basic knowledge of mathematics will suffice to your needs.”
4. Its tone?
Tone is friendly, conversational. Contractions are sometimes used. (see the quote in 3 above) The material is covered formally and professionally, but not stiffly.
5. Bias toward topic (sometimes called point of view)?
The point of view seems to be that the material covered in this book is easy to learn and yet very important.
6. Its style characteristics: passive vs. active voice, nominalizations, word choices (inappropriate jargon), grammar and punctuation problems, sentence structures (cohesive coherent, concise), etc.
The style of the document in relatively consistent and supports the persona and intended reader relationships effectively. There are several areas for improvement.
· Unnecessary passive voice could be revised to enhance the reader’s role in the processes described.
· Some of the ideas could be more clearly arranged in terms of ‘familiar to unfamiliar’
· Some subject verb agreement problems are found
The Celestial Line of Position
You have seen how you can use lines of position, obtained through bearings to objects on land, to fix the position of your ship when you are piloting. You know that a line of position (LOP) represents possible positions of your ship; in other words, your ship must be somewhere along that line. A fix, the intersection of two or more LOPs, is a relatively accurate determination of your ship’s latitude and longitude, but often does not represent the exact position of your ship because of observation and plotting errors and the uncertainties of tide, current and winds acting upon your ship.
In celestial navigation, as in piloting, you are essentially trying to establish the intersection of two or more lines of position. As a celestial navigator, you establish lines of position by observing heavenly bodies and applying the results. You cannot fix the position of your ship by a single observation and the resulting LOP. The most accurate method of obtaining a celestial fix is for you to take sights on many bodies in a short time. You will commonly take sights on six or more stars in a period of fifteen minutes or less. If you take sights on many celestial bodies you can identify and throw out LOPs that have obvious errors. If, however, you cannot obtain at least two good new LOPs, you may need to advance and intersect an old LOP with a new one in order to establish your fix.
You can use a line of position obtained at one time as part of a later fix; you create a running fix. All you need to do is transfer the line parallel to itself, the same distance and direction, on the chart, that the ship has run in the time since the observation. Of course your advanced LOP cannot be as accurate as a new line because you can only determine the amount and direction to transfer it by deduced reckoning. Naturally, the distance you may advance the old line without a substantial loss of accuracy depends on how accurately you have recorded and can reckon the run of the ship.
ORIGINAL:
You have seen how lines of position, obtained through bearings to terrestrial objects, are used to fix a ship’s position in piloting. You know that a line of position (LOP) is a locus of possible positions of the ship. In other words, the ship’s position must be somewhere along that line. A fix, by definition, is a relatively accurate determination of latitude and longitude. In practice, this position is the intersection of two or more lines of position; but often it is not the ship’s exact position because you can always assume some errors in observation, plotting and the like.
The celestial navigator must establish lines of position by applying the results of observations of heavenly bodies. A line of position obtained at one time may be used at a later time. All you need to do is move the line parallel to itself, a distance equal to the run of the ship in the interim, and in the same direction as the run. Such a line of position cannot be as accurate as a new line because the amount and direction of its movement can be determined only by the usual DR methods. If two new lines cannot be obtained, however, and old line, advanced and intersected with a new one may be the only possible way of establishing a fix. Naturally the distance and old line may be advanced without a substantial amount of loss depends on how closely the run can be reckoned.
In celestial navigation, as in piloting, you essentially are trying to establish the intersection of two or more lines of position. A single observation and the resulting LOP is insufficient to obtain a fix.
The most accurate method of obtaining a celestial fix is to take sights on many bodies in a short time. For example, it is quite common to take sights on six or more stars in a period of fifteen minutes or less. Taking sights on many bodies allows the observer to identify and throw out LOPs with obvious errors.
From: Quartermaster (US Navy Training Manual). US Government Printing Office.
Washington, D.C. 1995. Page 9-16.