So far, the price of any aeroplane of a well-known make has been high. An ordinary-type biplane, for example, fitted with a "Gnome" engine, has been selling for approximately £1000. A monoplane of established repute, built to carry a pilot alone, has been listed at £900. A military-type biplane, capable of carrying three men, has been selling at something like £1200, and a reconnoitring monoplane, for two occupants, has been priced at a figure in excess of£1000. There has, as a matter of fact, been good reason for manufacturers to demand high prices for their machines. The expenses of a builder of aeroplanes are extremely heavy. His business is not at all like any ordinary commercial undertaking. He does not merely build a machine, and then sell it. He has costly researches to undertake, and wearisome and expensive experimental work to carry out. Let us take a typical example. A prominent manufacturer in France designed a monoplane, which embodied improvements upon existing practice. Having the facilities of a well-equipped workshop, he speedily put his ideas to a practical test, and commenced the building of a machine. This occupied some weeks, during which time, of course, the builder had the wages of his engineers to pay. Then, when the machine was ready for tests, he had to hand it over to his professional aviator—another well-paid employee. The monoplane was taken to the private flying ground which the manufacturer found it necessary to rent; and here, for a week or so, first experiments were carried out, the wages of the aviator being augmented by those of a regular staff of mechanics. The result of the trials was that, after securing useful data, the monoplane was irretrievably wrecked, in landing after a flight. Whereupon, the manufacturer had to face the expense of building a second machine, embodying further improvements suggested—and going through the whole routine again. This he did, devoting several weeks of his men’s time to constructing the new machine. Once more, when it was finished, the professional aviator took it in hand. This time, after an even shorter career than the first machine, the monoplane was broken up. Again, however, improvements suggested themselves; and so the maker embarked, patiently, upon the construction of a third model. To cut a long story short, this process of evolution went on until six monoplanes had been built, each one more reliable in action than its predecessor. It was only, in fact, when a seventh machine stood ready, that the manufacturer considered he had a flying machine he could offer to prospective purchasers, as a safe and improved type.