From these results Baeyer concluded that Claus' formula with three para-**linkings** cannot possibly be correct, for the Q2.5 dihydroterephthalic acid undoubtedly has two ethylene linkages, since it readily takes up two or four atoms of bromine, and is oxidized in warm aqueous solution by alkaline potassium permanganate.

It was found that the results were capable of expression by the empirical relation CaH2b= 104.3b+49'09m+105.47n, where C a H 2b denotes the formula of the hydrocarbon, m the number of single carbon **linkings** and n the number of double **linkings**, m and n being calculated on the Kekule formulae.

Reduction to hexamethylene compounds necessitates the disruption of three of the edges of the octahedron, the diagonal **linkings** remaining intact, or, in the plane projection, three peripheral linkages, the hexamethylene ring assuming the form (III); In 1888 J.