Terence Aselford

In Ancient Rome, on the morning of his ninth birthday, young Martial Portius races against time to find his older brother Hershal. Unless Martial can deliver an important message to him, the forgetful Hershal will likely lose his job as a Roman courier. As Martial anxiously searches the crowded streets, he learns a good deal about the people, places, and customs of his native city.

Moreover Martial, the son of a poor artisan, comes to understand

Nineteenth century London is the center of a vast British Empire. Airships ply the skies and Queen Victoria presides over three-quarters of the known world—including the East Coast of America, following the failed revolution of 1775.
London might as well be a world away from Sandsend, a tiny village on the Yorkshire coast. Gideon Smith dreams of the adventure promised him by the lurid tales of Captain Lucian Trigger, the Hero of the Empire,

A trapped cosmic creature may drive the whole world mad—unless the spellsinger can set it free: “Foster knows how to spin a yarn” (Starlog).
It’s an ordinary day in the Bellwoods, save for the fact that Jon-Tom the spellsinger has awoken as a six-foot blue crab. He soon reverts to normal—as normal as a college student trapped in a world of magic and talking animals can be, anyway—but