Langley first published "Experiments in Aerodynamics" in 1891. This facsimile edition is based on the second edition published in 1902, as part of the "Smithsonian Contributions to Knowledge" volumes. It reports on Langley's early experiments in what he provisionally called aerodromics. "I have now been engaged since the beginning of the year 1887 in experiments on an extended scale for determining the possibility of, and the conditions for, transporting in the air a body whose specific gravity is greater than that of the air, and I desire to repeat my conviction that the obstacles in its way are not such as have been thought; that they lie more in such apparently secondary difficulties as though of guiding the body so that it may move in the direction desired, and ascend or descend with safety, than in what may appear to be the primary difficulties due to the nature of the air itself, and that in my opinion the evidence for this is now sufficiently complete to engage the serious attention of engineers to the practical solution of these secondary difficulties, and to the development of an art of mechanical flight which will bring with it a change in many of the conditions of individual and national existence whose importance can hardly be estimated." AIAA is pleased to bring this important book back into print.