Pliny the Elder stands in respect of date in much the same relation to Seneca as Plutarch does. His great work on Natural History, which was addressed to the reigning Emperor, Vespasian, was published in the year 77, that is, about a dozen years after Seneca’s death. We have already glanced at the bearing of this date upon that of the publication of the _Q.N._ We are now concerned rather with the relation of the contents of the two works. Gibbon (_Decline and Fall_, chap. xiii.) speaks of “that immense register where Pliny has deposited the discoveries, the arts, and the errors of mankind.” Nor is the description unjust. The work is of portentous length, extending to thirty-seven Books; it treats of an enormous variety of subjects, physical, geological, geographical, ethnographical, botanical, medical, etc., many of which are now quite dissociated from the title, _Natural History_. Pliny seems to have read everything that existed in writing on the various subjects included, and his array of authorities attached to the contents of each Book is very imposing.[23] But unfortunately his judgment does not appear to have been equal to his industry. Everything is recorded, credible and incredible, whether derived from trustworthy literature or based on mere report: a more uncritical congeries of truth and error it would be difficult to imagine. [23] He claims to have read about 2000 volumes of 100 choice authors, but his lists seem to include a much larger number of names--146 Roman and 327 foreign writers. See Teuffel, _Rom. Lit._ vol. ii., under Pliny the Elder. Cf. Dill, _op. cit._ p. 146 and _note_.