I insensibly plunged into the ocean of the Augustan history, and in the descending series I investigated, with my pen almost always in my hand, the original records, both Greek and Latin, from Dion Cassius to Ammianus Marcellinus, from the reign of Trajan to the last age of the Western Caesars.

The subsidiary rays of medals and inscriptions of geography and chronology, were thrown on their proper objects, and I applied the collections of Tillemont to fix and arrange within my reach the loose and scattered atoms of historical information.
Through the darkness of the middle ages I explored my way in the _Annals and Antiquities of Italy_ of the learned Muratori, and diligently compared them with the parallel or transverse lines of Sigonius and Maffei, Baronius and Pagi, till I almost grasped the ruins of Rome in the fourteenth century, without suspecting that this final chapter must be attained by the labour of six quartos and twenty years." When the time for composition arrived, he showed a fastidiousness which was full of good augury.

"Three times did I compose the first chapter, and twice the second and third, before I was tolerably satisfied with their effect." His hand grew firmer as he advanced.

But the two final chapters interposed a long delay, and needed "three successive revisals to reduce them from a volume to their present size." Gibbon spent more time over his first volume than over any one of the five which followed it.

To these he devoted almost regularly two years apiece, more or less, whereas the first cost him three years--so disproportionately difficult is the start in matters of this kind.
While engaged in the composition of the first volume, he became a member of Parliament.