Full accounts have now been published of the interesting experiments conducted by Professor S. P . Langley with his model “Aerodrome.” Both the “Strand Magazine” and “ McClure's Magazine” give almost identical accounts from the pen of the inventor, while in the “ Aeronautical Annual,” a somewhat more technical description is given.

These accounts go to show that which is so well understood by many of our readers, the extreme difficulty in the designing and constructing of such an apparatus. His well-known experiments with a whirling table gave the inventor valuable data to work upon, but the question of balance and behaviour in the air had to be studied, and this could hardly be done without constructing a complete working model, yet how could such a model be made until the principal conditions of flight were learned? So it seemed that the inventor was “ shut up in a sort of vicious circle.”

The two chief methods proposed by inventors for obtaining aerial flight are by means of aeroplanes or aerocurves, driven by screw propellers, and by wings worked as in nature.

Which of these designs will practically be best it is difficult to say. It can only be by actually trying the two methods that their merits can be compared. It may be that wings are the best, as they move a larger weight of air with less velocity than a screw propeller. The slip may on this account be less.

It may be that wings are the best, as they move a larger weight of air with less velocity than a screw propeller. The slip may on this account be less.

On commencing the study of .aeronautics it is above all things most important that we should make ourselves thoroughly acquainted with what has already been accomplished in order to save waste of effort on our part in trying experiments or devices already dealt with. Again, it is quite a mistake to suppose that but little, if anything at all, has as yet been accomplished towards the solution of this—the, perhaps, greatest of all mechanical problems. We do possess at last a science, of aeronautics, and a preliminary study of this same science is a sine quâ non; the successes and failures of the past must be carefully studied, as also the apparent causes of such successes and failures; and the principles involved— that is to say, the aerodynamical principles— must be above all things, most carefully studied, in order that the investigator may be perfectly enabled to distinguish between any inadequate proposal, certain to fail, and a design worthy of consideration, investigation, and, perhaps (after careful thought), a practical trial.