228 Notices respecting New Books. 



If you will not allow the power of the moon's attraction at 

 the earth's surface to be so much as my theory requires, you 

 at least cannot prove that it is not ; and, in that case, the only 

 fair way to determine the question is to ascertain which of the 

 ^wo theories comes nearest the truth. By comparing the dif- 

 ference between the high-water marks at spring and neap tides, 

 with the diiference between the low-water marks, it is easy to 

 ascertain what proportion the elevation bears to the fall. Now, 

 if there should be no difference between the rise and the fall, it 

 will be evident tliat the tides must be produced by pressure, 

 and not by expansion ; if the elevation should exceed the fall 

 in a very trifling degree, the effect produced by expansion 

 must be equally trifling ; but if, as 1 believe is the case, the 

 elevation should be twice as great as the fall, it must be evident 

 that one-half of the elevation is produced by expansion alone, 

 for there is no other principle that will produce this effect ; and, 

 as the rise of the other half, with its corresponding fall, must 

 be nearly, if not entirely, produced by a pressure, which is the 

 necessary consequence of this expansion, it follows that the 

 pressure of the waters, which is solelij dependent upon a diffe- 

 rence in the gravity of their particles, has either produced no 

 effect whatever, or, at the utmost, an elevation and fall which 

 are too trifling to deserve any consideration. 



Bath, March 12, 1833. Walter Forman. 



XLIX. Notices respecting New Books. 



"^ Table of the Circles, arising from the Division of a Unity 



or any other -whole Number, by all the Integers from 1 to 1024; 



being all the pure decimal Quotients that can arise from this 



Source ••" 8vo. pp. 118. 

 ** A Tabular Series o/" Decimal Quotients, foi- all the proper 



vulgar Fractions, of -which when in their lowest Terms, neithei- 



the Numerator nor the Deiiominator is greater than 1000 :" 



8vo. pp. 153. 

 JN our 47th volume, p. 385, and in our 51st volume, p. 137, 



we have briefly noticed the ingenious and vastly laborious 

 calculations of Henry Goodwyn, Esq. on the subject now fur- 

 ther prosecuted by the same gentleman, in the works before 

 us. The first of the thin volumes entitled as above, contams all 



the waters to the same height. As philosopliers can neither prove, on the 

 one hand, that the deep parts of the ocean do not ever exceed fifteen miles, 

 nor, on the other, that the moon's attraction at the earth's surface may not 

 be equal to the fiftieth part of the earth's, I cannot understand upon what 

 principle they found their objections to my theory. 



requisite 



