Many of our present-day magazine stories are of this type. Of the earlier modern, the "Diamond Lens" by Fitz-James O'Brien is interesting. "The Spider's Eye" is still sometimes read. "The Life Magnet" is well known. A burlesque verse tale of mechanical invention is "The Wonderful One Hoss Shay" by Oliver Wendell Holmes. The prince of all ingenious story-tellers, however, is Frank R. Stockton. To construct a narrative of this class, you must of course first get your underlying theory. Experiments in the chemical and physical laboratory will afford many a starting point. They will at least suggest the realm in which to proceed. Astronomy, meteorology, geology, mechanics, mineralogy, geometry, optics, domestic science even,--select a simple problem in any of these and begin to imagine. [Suggestions on how to write the type] After you have the starting point, it is a good idea to fix your goal. Where should you like to go, what should you like to do, what powers should you like to have above those of your fellows? Do you wish to overcome the restrictions of distance, absence, darkness, death, birth, poverty, the past, the future, the present? With these points of your theory settled, you must then look to the course of events. Shall the incidents befall you while discovering or while applying the scientific fact, while constructing or while working your machine? Shall you be looking forward or shall you be looking back upon the events? Next you must find the point of greatest stress. The climax of a story with the first alternative will evidently be reached at the culmination of the inventor's labors; with the second alternative, at the most exciting adventure in the use of the machine or in the direct application of the scientific fact. The logical close of the story is in both cases the disappearance of the machine or the scientist; but you will be repaid by thinking carefully over this matter and being here as elsewhere as ingenious and original as you can. Your deductions must appear to be sound. Of course, your reasoning may have to be largely specious and in the gross, as it were, unless you are a better inventor than the inventors. But you have this advantage over the practical man: you can avoid the greater difficulties by keeping silent about them; and for actual achievement you can substitute assertion. You must seem on the surface, however, to be perfectly logical. The reader will not question you too closely, if you are only spirited and entertaining. But the next is a point that you must note without fail.