Much appreciated! actually I've been lurking here for ages and this was one of the first threads where I thought I might have something to contribute.
On a second look, I fear I went a bit astray with the last part of the title. (A nonnullis/ Mediolanensis Athenaei sociis/ distributae)
I think it is more correctly rendered as "distributae by some (nonnuilis) members (sociis) of the Athenaeum of Milan".
The adjective "distributae" is the tricky word here. It *can* mean 'distributed', as in English, but it can also mean "sorted or classified". (Think of someone distributing stuff into different filing cabinets or pigeonholes.) As it is in the nominative plural, the only thing it can refer to is the "decisiones", not the book itself. So the best translation is probably "compiled". And in the line above, tractatus (discussed, read about) evidently refers to Index, so that line can be rendered as "indexed by topic or subject and with commentary".
Which gives us the title:
The Most Recent Decisions of the Sacred Roman Rota,
reduced to abstracts
indexed by topic, with commentary
in five volumes
compiled by members of the Athenaeum of Milan
(Can we render "nonnullis sociis" as "certain members" or even "leading members"?)
Now, who or what was this Milan Athenaeum? Athenaeum (the place of Athena) has long been a popular title for a learned society (ie one dedicated to the promulgation of wisdom of which Athena aka Minerva was patron). A well-known example is the Boston Athenaeum, but there is also one in the Vatican, the Athenaeum Pontificium Regina Apostolorum (the Papal Athenaeum of the Queen of the Apostles, ie the BVM) which is a training college for priests which was in the news a little while ago for offering courses in the history of satanism. (
http://news.bbc.co.uk/2/hi/europe/4272689.stm )
I discover (thanks to the wonders of google!)that the Milan Athenaeum still exists as a branch of the Catholic University of the Sacred Heart, its buildings being located near the Basilica of San Ambrogio, though in its present incarnation it appearently only dates from 1810. What its affiliations were in 1730 I haven't been able to find out; but if we had Volume One it would no doubt contain a preface explaining all. But I think we will find it was a secular body (at least as secular as such could be in Italy in those days) publishing independently of the papal authorities, as indicated by the absence of any imprimatur from them on the title page. (I suppose the Sacred Rota itself published/publishes its decisions in a regular gazette of some kind.)
If that is so, then the text accompanying the imprint of Mr Carl Joseph Gallus (or Gallo, as he most likely called himself) makes more sense. "With the permission of the superiors" simply means that the book has been passed by the (Milanese) government censors, and "with privileges" indicates that he had what we would now describe as a license, again from the Milanese government, to print and publish books.
So what we have is a reference book compiled by a learned society for the convenience of lawyers and students, and standing in the same relationship to Canon Law as a similar digest (with commentary) of recent decisions of the US Supreme Court compiled by, say, Harvard University would to the US Constitution and Acts of Congress. It isn't actually a book of Canon Law as such; and don't forget that back then the Pope was also the secular ruler of the Papal States, so many of the cases decided by the Rota would have dealt with purely secular matters like property disputes. That might account for Justice having a chalice -- not poisoned, or it wouldn't be haloed -- and a crown in her scales, indicating that in this case she is concerned with both sacred and secular law.
As for her bare boob -- an early example of the iconography that so shocked poor Mr Ashcroft -- that apparently suggests that Justice has nothing to hide, or words to that effect. It's her left boob, the side where her heart is... This picture isn't Great Art, remember; it's only a decorative illustration in a book, by a hack artist who would have worked from pattern books that gave standard iconography for artists to use when they had to depict abstractions like "Justice" or "Religion" or "Liberty" etc etc. He's transformed her (rather clumsily) into "Catholic Justice" by dumping a mitre and biretta on the ground next to her and giving her a chalice, and he may well have simply taken over the architect's instruments etc from some pattern book without giving them much thought.