As the month always precedes the next word, the abbreviation _OCT_ is aligned so that the two first letters are to the left of the printing point. In case a machine were equipped with numbers for all the days of the month, the character _14_ would be aligned to print either side of the printing point. As the abbreviation _09_ would always follow and never precede, it would be aligned with the _0_ in the printing point, with the _9_ printing to the right of it. It is very important to have special characters properly aligned so that the abbreviations which always _precede_ are aligned to print on the last letter, and the abbreviations which _follow_ are aligned to print on the first letter.
It is impossible to print abbreviations in solid matter such as a letter. They are only to be used in connection with dates of invoices or orders, in connection with names of firms. For instance, the abbreviation _Messrs._, at the beginning of a firm name where such a term is desired, or the abbreviation _Co._ at the end of a firm name or the abbreviations _Pr._, _Doz._, _Gro._, and similar abbreviations, come in the body of a bill and, preferably, in the first column after the quantity.
It should be remembered that when the rubber platen of a billing machine becomes worn and cut with holes incident to the use of periods, commas, hyphens, etc., the special character type will sometimes print heavy at the top and light at the bottom of the letter, or _vice versâ_. This is remedied to some extent by placing a new rubber roll on a cylinder billing machine, or a new rubber covering on a flat-bed billing machine.
Special characters are used to a better advantage on the under-stroke (or blind machine) than on the visible machine. In the latter, the type-bars are all grouped in less than a half circle, which necessarily crowds the type-bars a little closer together, and therefore does not permit of special characters of a large size.
=Tabulators on Billing Machines.= It is absolutely essential that every billing machine be furnished with either a single-stop (known as a _column-stop_) tabulator or a decimal tabulator, preferably the latter. A single-stop tabulator is used as follows:
On the billing machine frame rests a bar on which metal stops or pegs are placed at predetermined intervals. By pressing the column stop, the carriage holding the paper is released, and jumps automatically to the first stop. After the information is written, the stop is again pressed, and the machine jumps automatically to the next printing point. The following example shows the use of the column stop: