It will be noticed that compounds containing two double linkages will have the same general formula as the acetylene series; such compounds are known as the " diolefines."
From the fact that reduction products containing either one or two double linkages behave exactly as unsaturated aliphatic compounds, being readily reduced or oxidized, and combining with the halogen elements and haloid acids, it seems probable that in benzenoid compounds the fourth valencies are symmetrically distributed in such a manner as to induce a peculiar stability in the molecule.
Thus 0 2.4 indicates the presence of two double bonds in the molecule situated immediately after the carbon atoms 2 and 4; for example II.
Frederick afterward (in 1766) ordered from Shudi two double harpsichords for his new palace at Potsdam, where they still remain.
jasmine cottage: Sleeps 4. Two double bedrooms, both ensuite one with shower and one with bath.