at second hand
By an intermediary or by indirect means; usually relating to something heard, by hearsay.
at second-hand
The critic lives at second hand. He writes about. The poem, the novel, or the play must be given to him; criticism exists by the grace of other men's genius. George Steiner
To all those who lead monotonous lives in the hope that they may experience at second hand the delights and dangers of adventure. [author's dedication]. Agatha Christie