DR A. CRUM BROWN ON ISOMERIC COMPOUNDS. 710 



seems very unlikely that such a property of a substance so well known as succinic 

 cicid should not have been observed. 



We thus see, that the attempts to apply to the explanation of particular cases 

 the principle of a difference between the equivalents of multequivalent atoms 

 have failed, not, however, as far as can at present be seen, from any absurdity 

 in the principle itself, but rather from a want of well-observed facts to guide 

 us in its application. These we may expect before long, from the labours of 

 BuTLEiiow, ScHORLEMMER, and others, and we shall then be in a position to 

 form a definite opinion as to the form which this hypothesis should assume. 



VOL. XXIII. PART III. I) G 



