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almost infinitely improbable, viz., that, after the displacement, 
what Mr. Mallet calls the centre of adhesion shall have, in rela- 
tion. to the centre of gravity, such a position, that the moment 
of the weight of the displaced masses, referred to the centre 
of adhesion, shall have its original value, and tend, at the same 
time, to produce a motion of rotation opposite to that which 
has already occurred. Now, in order to this, the centre of 
adhesion must continue at the same side of the line of direc- 
tion of the earthquake-movement passing through thecentre of 
gravity of the displaced materials, and we must also have 
d xsin 0’ =d x sin 0’, d and d’ being the distance between 
centre of gravity and centre of adhesion before and after the 
first displacement, and @ and @’ the angles made by the direc- 
tion of earthquake-movement with the lines connecting centre 
of gravity with centre of adhesion. It is scarcely necessary 
to say, that the fulfilment of such conditions in any particular 
case must be in the highest degree improbable. 
The Secretary of the Academy read the second part of the 
Rev. Dr. Hincks’ paper on Phonetic Hieroglyphics : 
The object of the second part is to shew what data are 
most to be relied on for determining the exact powers of the 
Egyptian letters; the existence of an approximate alphabet is 
assumed, and the knowledge of facts grounded on the general 
correctness of this is to be applied to determine the exact al- 
phabet. Itis remarked, in the first place, that, as the powers of 
the letters probably varied at different times and in different 
parts of Egypt, it is necessary to assume a particular place 
and time, the alphabet of which is to be investigated. The 
place chosen is Thebes, and the time the interval between the 
deaths of the first and third kings of the name of Rameses, 
during which the principal sculptures at Thebes were exe- 
euted, and the papyri in the British Museum, of which fac- 
similes have been published, were written. The data which 
