NOTE FROM THE FRENCH EDITION OF 1893* 



I have already drawn the readers attention to the fact that the accompanying 

 figures only show a small part of the virtual work of the wind. It will be under- 

 stood that a diagram like that in our text, intended only to show the path of a body 

 in one given trajectory, cannot represent all the conditions of Nature, which are at 

 once much more favorable and much more complex, since I have here exhibited 

 out of many conditions one only, selected for the single reason that it is best fitted 

 to elucidate the fundamental idea of this treatise. 



So, too, I have spoken of a "plane" to aid my explanation, without meaning 

 that this form is actually best for flight, and without supposing that what has pre- 

 ceded about a perfected aerodrome could be misunderstood to mean that I would 

 actually employ only planes in such a machine, or employ them only under a con- 

 dition (that of a rectilineal- horizontal wind) used here merely to simplify the 

 enunciation of a problem. On the contrary I helieve the future aerodrome will 

 utilize not only the particular pulsation of the wind described here, but also its 

 ascending, lateral, and whirling motions. 



* " Le Travail Intcrieur du Vent." Revue de V Aironautique, 1893. 



