32 THE HAMILTON ASSOCIATION. 
When the Moon (M.) and the Sun (S.) are in conjunction as in 
Fig. 1, their combined attractions lift the volume of water W, from 
the solid earth and thus a high or spring tide is generated. Fur- 
thermore, the same effect is produced at the other side of the Earth 
inasmuch as the combined attraction of M. and S. pulls the Earth 
away from the water W2 and so leaves the water heaped up there, 
and thus here also a spring tide is generated. This is the position at 
new Moon on both sides of the Earth. 
Le ye eis 
w* ‘wi 
Mae A Gc ; 2a 2 
eae et 
Fig. 2. 
When the Moon (M.) and the Sun (S.) are in opposition as in 
Fig. 2, their attractions are opposed but still spring tides are pro- 
duced as before. This is so because the sun pulls the water W* 
from the solid mass of the Earth and also the Earth away from the 
water 2, and so leaving W2 heaped up. The Moon has similar 
effects on W2and W1. This is the position at full Moon on both 
sides of the Earth—the solar and lunar tides combine just as in 
Fig. 1. 
Fig. 3 
When the Moon and Sun are in quadrature or go° apart as in- 
Fig. 3, then the water is more or less equally distributed over the 
Earth for reasons evident upon an examination of the different 
attractions of M. and S. as explained with respect to Figs. 1 and 2. 
In this position the Sun and Moon attract separately and not in con- 
junction, and it is the same whether the Moon is go® east or 90° 
