[GAIUS libro primo institutionum. ] §1.7.2.prGeneralis enim adoptio duobus modis fit, aut principis auctoritate aut magistratus imperio.
[GAIUS in the first book of Institutes.] For general adoption is made in two ways, either by the authority of the emperor or by the command (imperium) of a magistrate.
principis auctoritate adoptamus eos qui sui iuris sunt: quae species adoptionis dicitur adrogatio, quia et is qui adoptat rogatur, id est interrogatur, an uelit eum quem adoptaturus sit iustum sibi filium esse, et is qui adoptatur rogatur, an id fieri patiatur.
By the authority of the emperor we adopt those who are sui iuris; which species of adoption is called adrogation, because both he who adopts is asked (that is, questioned) whether he wishes the person whom he is about to adopt to be a lawful son to him, and he who is adopted is asked whether he suffers this to be done.
imperio magistratus adoptamus eos qui in potestate parentis sunt, siue primum gradum liberorum optineant, qualis est filius filia, siue inferiorem, qualis est nepos neptis, pronepos proneptis.
By the command of a magistrate we adopt those who are in the power of a parent, whether they hold the first degree of children, such as a son or daughter, or a lower degree, such as a grandson or granddaughter, a great-grandson or great-granddaughter.
§1.7.2.1Illud utriusque adoptionis commune est, quod et hi qui generare non possunt, quales sunt spadones, adoptare possunt.
This is common to both kinds of adoption, that even those who cannot procreate, such as eunuchs, can adopt.
§1.7.2.2Hoc uero proprium est eius adoptionis, quae per principem fit, quod is qui liberos in potestate habet si se adrogandum dederit, non solum ipse potestati adrogatoris subicitur, sed et liberi eius in eiusdem fiunt potestate tamquam nepotes.
But this is peculiar to that adoption which is made through the emperor: that if he who has children in his power gives himself to be adrogated, not only is he himself subjected to the power of the adrogator, but also his children come into the power of the same person as grandchildren.