The Crustacea
The aquatic animals known as the Crustacea have no internal skeleton, but are defended by a strong crust, made of a series of rings. This unyielding armor, together with the coverings of the eyes, the tendons of the claws, and the lining membrane of the stomach, with its teeth, is cast off annually to permit the growth of the body. The Crustacea possess the power of reproducing a lost or original limb; and, indeed, if injured the animal itself shakes off the injured joint.
Suppose, now, that Dr. Wood found himself dissatisfied with these somewhat cramped and overloaded sentences, and determined to rewrite, making three paragraphs where he had formerly but one. In the new theme, the main topics would be, as before: Definition of Crustacea; Annual shedding; Reproduction of Limbs. Each would have a paragraph to itself, where before it had but a sentence. All the sentences to be made about the Definition would be set off by themselves as one main part of the theme; all those about the Shedding would form a second; all those about the New Limbs, a third.
“Set off”;—that is, by indentation, or indention. This word means, “a biting in,” or, more properly, “a biting out.” Where a new division of the theme begins, the first line does not come up plumb to the straight edge at the left; it is bitten into; it begins farther to the right than do the other lines. In the printed book, the indentation is small—usually the width of a letter m. But in a manuscript it is important for the indentation to be absolutely unmistakable. Some persons keep so ragged an edge at the left hand that it is impossible to know whether or not they should be credited with understanding what a paragraph is. Indent each new paragraph one or two inches. Bring every line of the paragraph, except the last, up even with the right-hand margin; the last line may be stopped anywhere, if the paragraph is complete in sense; often this line has but a word or two. If at any time you inadvertently omit the indentation, and have not time to copy, place a paragraph mark where the new paragraph should begin; thus, ¶.
A rough outline for Dr. Wood’s new paragraphs could now be made. The topics being known, the number of sentences under each could be guessed at. There is nothing in the original paragraph to show that Dr. Wood ascribed especial importance to some one of the three topics. The third is perhaps the least important. It may be estimated that in the completed theme he would give about 80 words to each of the first two, and about 50 to the third. The outline would be something like this, the full stops representing those of the future theme.
The Crustacea
¶ Crustacea are aquatic. No skeleton, but crust, which protects and strengthens. Framework of rings; part develops into limbs. Articulated animals.
¶ Curious way of growth. Other animals not inconvenienced as they grow. Not so Crustacea. Mail unyielding. Is cast off annually and larger coat grows. Eye-covering, tendons, stomach-membrane are also shed.
¶ Curious reproduction of lost or injured limb. New one grows if old lost; animal shakes off injured joint. Lobsters do, when alarmed.