Frontispieces are prints facing the title-page of books (with exceptions, of course) . As plates, they usually illustrate the content of the book with more or less complex iconographies, but in many occasions the plate shows a portrait. This can be of the author of the book but also of the person to which the edition is dedicated, or even the current regent of the place where the book was written or published, etc.
According to time and place portraits vary significantly. There can be found pictures where the portrayed is standing in an interior, is sitting beside a table, is enjoying the company of his family or friends, and so on. Though so far I have never encountered a portrait from behind.

At the moment I have little knowledge about this book, which is being sold here.
What is of absolute interest to me is the interaction it demands with the viewer. The motto on the scroll reads: “LOQUERE UT TE VIDEAM” which translated from Latin means: “Speak, so I can see you”.
So the portrayed gives us his shoulder, while he is looking outside of a window, overlooking a river with ships and some mountains in the background. He is wearing a wig which is finely detailed – look at the curl of hair popping from the head down to the top of his back, and how the hair is carefully parted in the half.
Riemer shows himself otherwise busy – as my Literature teacher used to say when she caught someone red-handed, not paying attention to her lecture – enjoying the view of Leipzig (?) from his work place (??). Nevertheless, he left the choice of disturbing him from his thoughts to the reader or anyone willing to engage a conversation with him on poetics, rhetoric and style.
I am curious: [tap, tap on the shoulder] “Herr Riemer?… may I just…” [to be continued…]
P.S.: if you are wondering how he looked beyond his wig, here is a nice portrait of Mr. Riemer by Christian Froberger, published by Christian Romstet in 1687.