FIRST PRINCIPLES OF AERIAL TRANSIT. 
36a 
from a rifle, and propelled a mile distance in one second, it will 
still descend sixteen feet during its passage, falling as before in 
the same time. 
If the ball is fired on the level of perfectly smooth water, it 
will not sink till the force is nearly expended. It would remain 
above water without sinking as long as the velocity was main- 
tained. This arises from the fact that the ball, in its swift 
passage over the surface, meets with so many particles in a brief 
period, that there is no time to give them motion, and, in con- 
sequence, the water stratum is not deflected or does not yield 
under such a speed ; therefore the ball continues to traverse as if 
on a solid plane. This being illustrative of a main principle of 
flight, will be referred to again under a modified condition. 
Assuming, from our knowledge of elementary laws, that there- 
is no principle in any form of motion that can be given to a. 
weight within a body in free space that will create a persistent 
force in one direction only, so as to counteract the action of 
gravity due to the earth’s attraction, and that weight is an 
absolute condition of ail tangible matter, it follows that in flight 
the air alone must be considered as the sole medium of support. 
Eapid transit at the will of the aeronaut is the main condition 
worth consideration, as a subject of general utility ; aerostation, 
implying the use of large volumes lighter than an equal bulk of 
air — exemplified by the various forms of balloons — may be 
excluded from the argument, as the inconveniences attendant 
upon their use, and their enormous size, renders anything like 
speed of propulsion impracticable — precluding all hopes of im- 
provement or discovery in this direction as a means of loco- 
motion to be generally employed by man. 
The laws of flight, in the true sense of the term, must be 
considered entirely upon the resistance of the atmosphere, and 
based upon its principles of action and reaction, implying the 
impulse of a very light body — such as air — affording support to 
one of far greater density — such as that of a bird — with the 
least possible expenditure of power, the aerial stratum forming 
a roadway that levels all terrestrial obstacles, and one that will 
not yield during the passage in flight to a degree causing an 
undue expenditure of force. 
According to the laws of action and reaction in two bodies in 
motion towards each other, if they are components of different 
weights or densities, and as time is always an element in the 
determination of the value of mechanical power, it follows that, 
to maintain equilibrium, the impulse or opposing force must be 
obtained from the reaction of a larger body of the lighter 
element during a given period ; and as in the case of flight the 
abutment has to be secured upon the .yielding air, and the re- 
action effected by the resistance of an extensive surface, we 
