Once the topic sentence is written, the idea the paragraph
is about must be developed. This part of the paragraph is sometimes
called the body and develops the evidence, data, and/or logic that supports
the idea the paragraph has taken up. Usually, figures, tables,
and data as well as logic are used to support the point of the paragraph.
These data are critical to the argument and the reader should not be
left to their own devices to figure out what the data show. Write about
the figure or table. A simple parenthetical citation which sends the
reader to the figure or table is often inadequate. Make clear what
the data show and how the figure relates to the paragraph topic. Because
each paragraph should have a topic sentence, a body, and a concluding sentence,
paragraphs should rarely be one to two lines long. Each paragraph
should contain support for the topic of the paragraph.
After the body of the paragraph is developed there should
be a concluding sentence. This sentence is in the emphasis position
in the paragraph (Gopen and Swan, 1990) and should be related to the paragraph.
A common error is to introduce new material in the concluding
sentence of a paragraph. This often leaves the reader surprised because
main point of the paragraph is expected in the emphasis position. The
concluding sentence should reiterate and clearly state the main point the
paragraph makes.
A technique which can help create good paragraphs is to identify the function of a paragraph. Analysis of what the paragraph does and says is often useful. The distinction between what a paragraph does and says is important and can be clarified with some examples from English. Words that describe what a paragraph does include: describe, trace, compare, analyze synthesize,..... . Thus the paragraph you are currently reading describes the difference between what a paragraph does and says. A statement of what a paragraph says is harder to subsume with single words, but again can be illustrated through the paragraph you are now reading. This paragraph says that there is a difference between what a paragraph does and what a paragraph says, and that analysis of a paragraph's function may help the writer write more clearly. Note that what the paragraph does and what it says are different. The "says" identifies the idea the paragraph intends to convey; the "does" is the mechanism by which the paragraph conveys the thought. By reviewing your own paragraphs and analyzing what they do and say, you can often clarify your writing so that the reader can better follow your argument.
In general, a paragraph should contain a transition which connects the paragraph with what has gone before with what is to come, a clear topic sentence, and a clear, and smooth development of the paragraph topic which leads to a conclusion. The paragraph does not have to develop an earth shaking idea, but may be a transition itself which clarifies where the reader has been and directs the readers attention to a new topic related to the previous material. The writer should clearly convey what the paragraph is trying to "say" and should recognize what the paragraph is "doing" to convey the idea. Such a paragraph functions to direct or lead the reader through the argument to the conclusion the writer plans.
The settlement of the southern California mountains after statehood and the advent of newspapers brought increasing information on mountain fires. The earliest detailed accounts come from the western San Bernardino Mountains, where fire was a direct threat to the primary timber resource of southern California (Minnich 1988). san Bernardino newspapers even specified the canyons involved. Ten burns were reported in various portions of Waterman Canyon between 1870 and 1919; 13 were reported in City Creek (Fig. 1). Numerous fires were reported in the mountains in 1858, 1876, 1878, 1879, 1881, and 1889.
In the San Gabriel Mountains, which remained unpopulated until c. 1890,
smoke annually elicited numerous comments in the Los Angeles newspapers, especially
in relation to Indians, weather, or the beauty of the spectacle (Table 1).
The typical news observation was a vague statement that fires were raging
in the mountains. The language suggests t hat burning was an ordinary circumstance
and persisted for considerable periods. Fires were sometimes viewed as the
cause of heat waves, because they apparently tended to grow larger and produce
more smoke in hotter weather. Most fires occurred in summer although some
reports extended into the Santa Ana wind season after September. Many fires
were probably overlooked during cooler weather when views of the mountains
were obscured by low morning clouds and afternoon sea haze. Most smoke columns
were probably ignored."
One locality in which the rate of growth of such crystallites has been studied is Deep Spring Lake, located on the California-Nevada state line (Peterson et al., 1966). No whitings have been seen but dolomite crystals, mostly less than 1 µ in size, are abundant on the lake bottom. Detailed C14 measurements have been made of this dolomite. The age of various size fractions from the sediment was determined and, in every case, the coarser sizes had a greater average age. The rate of growth of the crystals ranged from 0.05 to 0.09 µ/1000 y, which is extremely slow compared to growth rates of most substances from saturated solutions.
X-Ray diffraction studies of different layers within the dolomite crystals revealed that the surficial layer(s) on the growing crystal is (are) calcium-rich but that 1:1 stoichiometry of magnesium and calcium ions is achieved by short-range solid state diffusion before the inner part of the crystal is buried too deeply inside the crystal and effectively isolated from the growth medium.
Deep Spring Lake is perhaps the closest approach to documented primary dolomite yet reported but if primary dolomite is defined as spontaneous nucleation from a body of natural water, not even the Deep Spring occurrence qualifies. The dolomite crystals in the lake appear to result from metasomatism of calcium carbonate at the sediment-water interface and the process here seems to require time periods of tens or hundreds of years to occur. Clearly, a time interval of this duration is irresolvable in ancient rocks. For this reason, some geologists would refer to the Deep Springs dolomite as primary and the correctness of this usage is largely a semantic question."