The book is built on a decimal plan, the material being simplified and reduced to one hundred articles. Headings of these articles are summarized on two opposite pages by a chart. Here the student can see at a glance the resources of the volume, and the instructor can find immediately the number he wishes to write in the margin of a theme. The chart and the decimal scheme together make the rules accessible for instant reference.

By a device equally efficient, the book throws upon the student the responsibility of teaching himself. Each article begins with a concise rule, which is illustrated by examples; then follows a short "parallel exercise" which the instructor may assign by adding an x to the number he writes in the margin of a theme. While correcting this exercise, the student will give attention to the rule, and will acquire theory and practice at the same time. Moreover, every group of ten articles is followed by mixed exercises; these may be used for review, or imposed in the margin of a theme as a penalty for flagrant or repeated error. Thus friendly counsel is backed by discipline, and the instructor has the means of compelling the student to make rapid progress toward good English.

Although a handbook of this nature is in some ways arbitrary, the arbitrariness is always in the interest of simplicity. The book does have simplicity, permits instant reference, and provides an adequate drill which may be assigned at the stroke of a pen.

When a number is written in the margin of your theme, you are to turn to the article which corresponds to the number. Read the rule (printed in bold-face type), and study the examples. When an r follows the number on your theme, you are, in addition, to copy the rule. When an x follows the number, you are, besides acquainting yourself with the rule, to write the exercise of five sentences, to correct your own faulty sentence, and to hand in the six on theme paper. If the number ends in 9 (9, 19, 29, etc.), you will find, not a rule, but a long exercise which you are to write and hand in on theme paper. In the absence of special instructions from your teacher, you are invariably to proceed as this paragraph requires.

Try to grasp the principle which underlies the rule. In many places in this book the reason for the existence of the rule is clearly stated. Thus under 20, the reason for the rule on parallel structure is explained in a prologue. In other instances, as in the rule on divided reference (20), the reason becomes clear the moment you read the examples. In certain other instances the rule may appear arbitrary and without a basis in reason. But there is a basis in reason, as you will observe in the following illustration.

Suppose you write, "He is twenty one years old." The instructor asks you to put a hyphen in twenty-one, and refers you to 78. You cannot see why a hyphen is necessary, since the meaning is clear without it. But tomorrow you may write. "I will send you twenty five dollar bills." The reader cannot tell whether you mean twenty five-dollar bills or twenty-five dollar bills. In the first sentence the use of the hyphen in twenty-one did not make much difference. In the second sentence the hyphen makes seventy-five dollars' worth of difference. Thus the instructor, in asking you to write, "He is twenty-one years old," is helping you to form a habit that will save you from serious error in other sentences. Whenever you cannot understand the reason for a rule, ask yourself whether the usage of many clear-thinking men for long years past may not be protecting you from difficulties which you do not foresee. Instructors and writers of text books (impressive as is the evidence to the contrary) are human, and do not invent rules to puzzle you. They do not, in fact, invent rules at all, but only make convenient applications of principles which generations of writers have found to be wisest and best.