334 THE BORDERLAND OF SCIENCE. 



rested by an account of the relations which have been 

 observed to hold between the weight and the support- 

 ing surface of different winged creatures. 



We owe to M. de Lucy, of Paris, the results of the 

 first actual experiments carried out in this direction. 

 The following account of his observations (made in the 

 years 1868, 1869) is taken from a paper by Mr.Brearey, 

 the Honorary Secretary to the Aeronautical Society. 

 ' M. de Lucy asserts,' says Mr. Brearey, ' that there is 

 an unchangeable law, to which he has never found any 

 exception, amongst the considerable number of birds 

 and insects whose weights and measurements he has 

 taken, viz., that the smaller and lighter the winged 

 animal is, the greater is the comparative extent of 

 supporting surface. Thus in comparing insects with 

 one another the gnat, which weighs 460 times less 

 than the stag-beetle, has 14 times greater relative 

 surface. The lady-bird, which weighs 150 times less 

 than the stag-beetle, possesses 5 times more relative 

 surface, &c. It is the same with birds. The sparrow, 

 which weighs about 10 times less than the pigeon, has 

 twice as much relative surface. The pigeon, which 

 weighs about 8 times less than the stork, has twice as 

 much relative surface. The sparrow, which weighs 339 

 times less than the Australian crane, possesses 7 times more 

 relative surface, &c. If we now compare the insects 

 and the birds, the gradation will become even more 

 striking. The gnat, for example, which weighs 97,000 

 times less than the pigeon, has 40 times more relative 

 surface ; it weighs 3,000,000 times less than the crane 



