RECENT AERONAUTICAL PROGRESS. 128 



veiy special merit, a'lid by explaining- these I hope to enlist their sym- 

 patic and support to the movement. For I have before now been 

 asked: '" Why should itbe necessar}' to have a society for the study of 

 ac^'ial navigation? AMiere is the importance of iti AVhy not institute 

 a society for submarine navigation, for wireless telegraphy, or for the 

 encouragement of any other novel invention for the improvement of 

 means of communication or warfare?" But useful as many such 

 inventions may be, none can have the great importance which may 

 some day be attached to the machine which navigates the air. 



And there are two reasons why this subject is a large one. The tir^t 

 is that the science of aeronautics is one combining many branches and 

 spreads into many ramitications. We have aerial machines as they 

 exist to-day. The balloon, forming a unique and fascinating mode 

 of tra\'el, enables us to mount high into the skies to obtain glorious 

 views of earth and cloudscape, giving us a laboratory for the study of 

 many intricate problems of the atmosphere, and forming a valuable 

 instrument of war. We nuist study how this passive buoy may be 

 impro\'ed upon, what new materials may l)e applied to its construction, 

 gases, methods for causing it to rise and sink, and means of directing 

 it out of the course of the wind. But we also have the more diHicult 

 })roblem of how to drive it through the air so as to make it inde- 

 pendent of the wind and go in any desired direction. Closely con- 

 nected with this is is the subject of kite Hying, whether for man lifting 

 or meteorological observation, of parachutes, and of soaring machines. 

 All these necessitate a certain knowledge of the various branches of 

 meteorology, which is to aeronautics as hydrogaphy is to marine nav- 

 igation. Then we have the studv of birds and other tiding animjds as 

 a natural se([uel to the science. 



The second reason for the importance of this su))ject is the vast 

 future which appears open to it. If such an a])paratus can be con- 

 structed as will enat)le man to make pr;u-tical use of the highway of 

 the air, there is promise of the sut)ject becoming of even more impor- 

 tance than marine navigation or railways. 



We have, then, not merely to consider the ))r()ad principles of the 

 general form of the aerial machine of the future — whether it is to take 

 the shape of an artiticial bird, a propelled kite, or a dirigible l)ailo()n. 

 We have to study the subject of aerod3'namics, the effect of air pres- 

 sures on plane or curved surfaces traveling at various speeds and at 

 various angles of incidence. We have to investigate the efficiency of 

 aerial propellers of ditierent forms, the strengths of materials, the 

 energy and weights of various forms of motors. Then we must also 

 study the natural currents of air, the variability of air strata, the 

 trends of winds, and so on. 



The great range of su))jccts to be gone into by our society is thus 

 patent. Many of our members and others are busily at work in some 



