350 NOVUM One A NUM. 



The motion by which waters rise in flood and sink in ebb, without 

 any accession of external waters, must of necessity take place in one 

 of these three ways : either there is a supply of water emanating from 

 the interior of the earth, and retiring into it again ; or the mass of 

 water is not augmented, but the same waters are extended (without 

 receiving any addition to their quantity) ; or rarefied, so as to fill a 

 larger space and dimension, and contract themselves again ; or there 

 is no increase either of quantity or of extension, but the same waters 

 (just as they are in quantity and density) are raised by sympathy with 

 some magnetic force attracting them from above, and then fall back 

 again. And so (the two former motions being dismissed) our con 

 sideration may now be reduced to this point, and we may ask if any 

 such elevation by sympathy or magnetic force does take pkice. Now, 

 in the first place, it is manifest that the whole of the water, as it is 

 disposed in the trench or hollow of the sea, cannot be raised at the 

 same time, there being nothing to supply its place at the bottom ; so 

 that, even if there were in water any such desire of rising, it would be 

 broken and checked by the connection of things, or (as it is commonly 

 called) the abhorrence of a vacuum. It remains that the waters are 

 raised on one side, and are thereby diminished and retreat on 

 another. Again, it will follow of necessity that that magnetic force, 

 since it cannot act upon the whole, will operate with the greatest 

 intensity about the middle, so as to raise the water in that part ; and 

 as that is raised, the sides are necessarily deserted and left bare in 

 succession. 



Thus we have at length arrived at an Instance of the Cross on this 

 subject. And it is this. If it be found that during the ebb of the sea 

 the surface of the waters is more arched and round, owing to the rising 

 of the waters in the middle of the sea and their falling away at the 

 sides, I mean the shores ; and that during the flood the same surface 

 is more level and even, owing to the return of the waters to their 

 former position ; then indeed, on the strength of this Decisive Instance, 

 the raising by magnetic force may be received ; otherwise it must 

 be entirely rejected. Now, trial of this might without difficulty be 

 made in the narrow seas by means of sounding lines ; that is to say, 

 whether during ebb the sea be not higher or deeper towards the middle 

 than during floods. It must, however, be noted that, if this be the 

 case, the waters must (contrary to the common belief) rise during the 

 ebb and sink during the flood, so as to cover and wash the shores. 



In like manner let the Nature inquired into be the Spontaneous 

 Motion of Rotation, and especially whether the diurnal motion, by 

 which the sun and stars rise and set to our view, be a real motion of 

 revolution in the heavenly bodies, or an apparent motion in the 

 heavenly bodies and a real one in the earth. We shall find, on this 

 subject, the following Instance of t/.e Cross. If there be found any 

 motion in the ocean from east to west, however weak and languid ; if 

 the same motion be found a little brisker in the air, especially within 

 the tropics, where it is more perceptible, on account of the greater 

 circles ; if the same motion be found in the lower comets, but now 



