3 4 
REACTIVE LOCOMOTION. 
rufhing into vacuum, or trying to, juft as really as the wind 
moving at the rate of 884 miles an hour. 
But for the vacuum centre in the fan-blower the man’s 
hat would not have floated: and but for the vacuum 
centres fomewhere in the atmofphere, we fhould have no 
winds and no bird-flying: and but for the vacuum centres 
produced by the wings of infects of the dragon-fly type, no 
infe<ft locomotion in the air. Air-locomotion relates to 
vacuums, and wind-preflures the refult of vacuums; and 
whether thefe vacuums arife from folar heats at the equator 
or ice at the poles, or both, producing winds, wind-preflures, 
and bird-flying; or from the magazines of heat and force 
within the bodies of the infects themfelves, producing 
winds, wind-preflures, and Readtive Paflive locomotion 
—the law is ftill the fame,— vacuum-originated-force the 
fulcrum and foundation of air-locomotion , for every living 
creature of the air, from the lady-bird that floats on a 
breath to the eagle that floats on a blaft. 
The bird-world holds a monopoly of the vacuum 
forces of the firmament; the infedvworld (typified in 
the dragon-fly) rely upon the forces created by themfelves. 
It remains for man to imitate the infe<ft, regarded as an 
animated fan-blower; but by no fuch clumfy imitations as 
thofe with which he has attempted to imitate wings. The 
mechanical fan-blowers contrived by man are not to be 
compared with the mechanical fan-blowers contrived by 
man’s Creator. The material to be dealt with is air; 
