According to the intelligence he gathered, the productivity and technological level of this world in 1792 roughly equates to the early to mid period of the first industrial revolution before his transmigration.
Perhaps it's the particularly nourishing small grains of the Otherworld, or perhaps the different gravity, but the average physical quality of people and animals on the Theia Plane is noticeably stronger than in the pre-crossing world.
Besides, due to the existence of Magic and alchemy and the exhaustion of petrochemical energy, the technological tree on the Theia Plane is heavily skewed.
Industry is on a single line, that is, boiling water — ahem, steam power.
Gigantic, noisy, crude steam engines are the mainstream machinery in this world.
High-Level technology basically relies on archaeological excavation.
Whoever can find relics from previous eras and excavate precious tomes can gain technological power surpassing the times.
