34 THE HAMILTON ASSOCIATION. 
iC = CE, =1and 2M = so. 
Now the attraction at /, exceeds the average 
it I 
by —— — —- which = .000,009,49 ; 
59 (00) 
but —— = ,000,0€9,26 ; 
.. the difference nearly = ——. 
60° 
Again, the attraction at #2 exceeds the average 
I I 
by —— — —~— = 000,009,03 ; 
60° 61" 
2 
which nearly = —-. 
60° 
These two over balances are therefore nearly equal and vary 
inversely as the cube of the distance of the Moon from the Earth. 
The law therefore is that the tide generating force varies directly as 
the mass and inversely as the cube of the distance of the mass 
M 
or Fao — 
JOP 
To compare the tide-generating forces due to Sun and Moon 
Mass of the Sun = 331,000 Earth mass 
Mass of the Moon = ; Marth mass 
Sun’s distance = 390 Moon’s distance 
331,000 
Solar tide-force 390° 
Lunar tide-force I 
81 
331,000 SI 331 2 
39° X 1000 I BOAT Gt I 
