Terminus Est is a sword in the science fiction series The Book of the New Sun by Gene Wolfe. It is wielded by Severian, a torturer and the narrator of the series.
In the Shadow of the Torturer, after Severian is expelled from his guild and the city of Nessus for showing mercy to one of his charges, he is sent north to serve as a carnifex in a different city. A carnifex is an executioner, and may also perform excruciations. Officially, Severian remains a journeyman torturer, to conceal the disgrace he has brought upon the guild. Before Severian leaves, Master Palaemon gives him Terminus Est. A sharp, intimidating sword, it serves as a symbol of his authority and as a deadly weapon. Despite its utility, the sword is apparently extremely ostentatious, as "art had been lavished upon her," according to the narrator.
Terminus Est is described as being "Light to raise, weighty to descend," by Master Palaemon. This is due to a channel in the spine of the blade, containing liquid hydrargyrum...
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