Mandicstcr Memoirs, Vol. xiiv. {igoo), No. II. 3 



experience that I am free to confess that, durin;^ a some- 

 what lengthy career as an experimcntaHst, I have accu- 

 mulated a considerable stock of negative knowledge, both 

 in pure and applied science. 



6. One of the branches of unsuccessful experiment in 

 which I was engaged at intervals for many years was an 

 investigation into the possibility of aerial locomotion. The 

 interesting lecture on "The Mechanical Principles of 

 Flight," recently delivered before the Society by Lord 

 Rayleigh, emboldens me to bring forward a brief summary 

 of the results of my investigations, with the intention that 

 they may be utilised to lighten the path of those adven- 

 turous experimenters who may attempt the solution of 

 the fascinating problem of navigating the aerial main. 



7. The literature of aeronautics is now very extensive, 

 and the subject has of late years been investigated, both 

 theoretically and experimentally, by men of the highest 

 scientific attainments. It will be sufficient to mention 

 the names of Dr. Pettigrew, F.R.S., of Edinburgh, MM. 

 Marey and Tissandier, in France, and Prof Langley and 

 Mr. O. Chanute, in America. The last named is an 

 eminent civil engineer, whose recent work on Progress 

 in Flying Machines is the most complete epitome of the 

 history and principles of aviation that has }'et been pre- 

 sented to the world. 



8. Omitting from the purview of this paper the legends 

 of antiquity like those of Daedalus and Apollonius Tyanaius, 

 in which men \vere reputed to have aviated and been 

 levitated above the earth's surface, either with or without 

 the aid of mechanical appliances, the first serious attempt 

 to study the problem of aerial locomotion was made about 

 1500 by Leonardo da Vinci, who not only proposed to 

 provide man with wings, but also experimented with paper 



