Hopkins constructed his multiplying mechanism on the Bollee scheme of using stepped controlling plates for his reciprocating racks to give the multiples of the digits, but the ingenious method of application shown in the Hopkins patent drawings illustrates well the American foresight of simplicity of manufacture. During the past ten years there have been a large number of patents applied for on mechanism containing the same general scheme as that of Bollee and Steiger, but up to the present writing no machines with direct multiplying mechanism have been commercialized except “The Millionaire,” which is non-recording, and “Moon-Hopkins Bookkeeping Machine.” A Closing Word As previously stated, it is impossible to describe or illustrate the thousands of inventions that have been patented in the Art of accounting machines, and some of the inventors may feel that the writer has shown partiality. The subject of this book, however, has to do only with the Art as it stands commercialized and those who are responsible for its existence. In the arguments to prove validity of contributions of vital importance to the Art, many other patented machines have been used which really have no bearing on the Art. But the writer was obliged to show their defects, otherwise the misconception derived from articles written by authors incompetent to judge would leave the public in error as to the real truth relative to the Art of the modern accounting machines. That all inventors deserve credit, even in the face of failure, is without question. The hours, days, months, and sometimes years, given up to the working out of any machine, intended to benefit mankind, whether the result brings a return or not,--whether the invention holds value, or no,--leaves a record that the world may benefit by, in pointing out the errors or productive results. If it were not for the ambitions and untiring efforts of men of this type, who give heart and soul to the working out of intricate problems, the world would not be as far advanced as it is today. The writer has kept in close touch with the Art of calculating machines since 1893, and made exhaustive research of it prior to that period. There have been thousands of patents issued on machines of the class herein set forth, but outside of the features reviewed there have been no broadly new ones of practical importance that have as yet proved to be of great value to the public. What is in the making, and what may be developed later, is open to conjecture. It is a safe conjecture, however, that in the present high state of the Art it will tax the wits of high-class engineers to offer any substantial and broadly new feature which will be heralded as a noticeable step in the Art. And that, as in the past, thousands of mistakes, and impractical as well as inoperative machines will be made and patented, to one that will hold real value. [Illustration] Index to Subjects