406 
[May 16, 
SOLAR AND PLANETARY ROTATION. 
3¥ Puiny EARLE CHase. 
(Read before the American Philosophical Society, May 16th, 1872.) 
The similarity in the length of day, between the principal and sub- 
ordinate planets, both in the intra and the extra-asteroidal belt, is so 
obvious, that many attempts, of which Kirkwood’s is the most satisfactory, 
have been made to formulate it. 
Ihave long thought that there is some simple explanation for the 
rotation, as well as for the revolution of the heavenly bodies. My recent 
investigations of explosive gyration, have yielded some interesting results, 
which, from their relation to the most important bodies of our system, 
encourage me to hope for further and more minute developments of a 
like kind. 
1. The sidereal revolution of the Moon : the sidereal rotation of the 
Harth, nearly :: the equatorial value of g at the Sun : the equatorial 
value of g at the Earth. 
27.3669--27.292—1.00275. 
2. The action of terrestrial superficial gravity against a uniform 
opposing force for a sidereal half-day, would be sufficient to give a 
velocity equivalent to that of a planet near the Sun’s surface. 
43, 0827—261.8164 miles ; 265.5184 :261.8164—1.01414, which is nearly 
equal to 1+-the Earth’s orbital eccentricity. 
3. The action of the superficial gravity of Jupiter for a sidereal half- 
rotation, would also be sufficient to give a velocity equivalent to that of 
a planet near the Sun’s surface. 
18,863 2.419—=276.247; 276.24'7-+-265.5184. 1.0406; which is nearly 
equal to 1+Jupiter’s orbital eccentricity. 
4, The action of solar superficial gravity for a sidereal half-rotation, 
would give nearly the velocity of light. 
2 Of 25.1868 86, 4007 —180,465 ; 183,454 + 180,465 — 1.0166. 
5. The action of terrestrial gravity, near the Earth’s surface, for a 
sidereal year, would also give a velocity equivalent to that of light. 
31,558, 150g—191,792 ; 191,792+183, 454 1.04545, which is nearly equal 
to 1+-Jupiter’s orbital eccentricity. 
6. The orbital radius of Saturn : Mercury’s orbital radius, nearly :: time 
of sdlar rotation : time of terrestrial rotation. 
9.53885 +. 3871 24.642 ; 25.187-+-24.642—1.0221. 
- The distance of Neptune from the Sun, is nearly equivalent to one- 
fourth the orbit of Uranus. 
19.1826397 
Go 
+ 80,037 — 1.00233. 
9 
a 
8. The mass of the Sun : the mass of the Earth, nearly :: cube of 
Karth’s orbital radius : cube of Sun’s semi-circumference, 
(214.86 +7)8 319,894 ; 319,894 + 314,000—1.01878. 
a 
ising iimnesioie 
