Rejuvenate and revive

Meaning

Rejuvenation is among the extraordinary medical effects reported by the main treatise: restoring old people’s lost strength and reviving the half-dead. The author immediately declines to develop these claims because he is no physician and leaves judgement to those who possess and know how to use the medicine. The English “It is said” appropriately marks the reported character before that qualification. Erquicken here means revive or refresh, while halb todten means half-dead, not people stated to be finally dead. The passage does not override the introduction’s explicit denial that a material restorative can free the body from mortality.