There are so many millions of organic compounds that simply finding names for them all is a major challenge. It was not until the late nineteenth century that chemists developed a logical system for naming organic compounds. Compounds had often been named according to their sources. The 1-carbon carboxylic acid, for example, was first obtained from ants, and so it was called formic acid, from the Latin word for ants ( formicae ). The 2-carbon acid was obtained from vinegar ( acetum in Latin), and was called acetic acid.
5. Central loading: Whereas modern stories are usually presented in a clear, linear fashion with the climax occurring near the end, ring compositions tend to place the climax or central crisis of the narrative in the middle (with the parts proceeding the middle moving towards it, and the parts following the middle moving away from it). “One clue that the middle has been reached,” says Douglas, “is that it uses some of the same key word clusters that were found in the exposition. As the ending also accords with the exposition, the mid-turn tends to be in concordance with them both. Then the whole piece is densely interconnected.” 26 In addition, the most important message of the work tends to be delivered at the turn or the center of the ring.
A more recent variant of this type of theory by R. M. Canup is that the rings could represent part of the remains of the icy mantle of a much larger, Titan-sized, differentiated moon that was stripped of its outer layer as it spiraled into the planet during the formative period when Saturn was still surrounded by a gaseous nebula.   This would explain the scarcity of rocky material within the rings. The rings would initially have been much more massive (≈1,000 times) and broader than at present; material in the outer portions of the rings would have coalesced into the moons of Saturn out to Tethys , also explaining the lack of rocky material in the composition of most of these moons.  Subsequent collisional or cryovolcanic evolution of Enceladus might then have caused selective loss of ice from this moon, raising its density to its current value of g/cm 3 , compared to values of for Mimas and for Tethys.