Rick Seddon wrote:

> Good thought abut Urania in Purgatorio. Interestingly the "Temple
> Classics" edition of "Purgatorio" that TSE carried in his pocket puts
> that canticle thusly:
>
> Now 'tis meet that Helicon for me stream forth
> and Urania aid me with her choir to set in verse
> things hard to conceive.
>
> Note the last word "conceive" fits nicely into the context of your
> reading.


While the translation including the word "conceive" fits the context,
I don't think the original nor other translations do. I doubt that
the Italian "pensar" is used or was used in any kind of way for
physical conception.


Dante:

Or convien che Elicona per me versi,
  e Uranie m'aiuti col suo coro
  forti cose a pensar mettere in versi.


Longfellow:

Now Helicon must needs pour forth for me,
  And with her choir Urania must assist me,
  To put in verse things difficult to think.


Norton:

O Virgins sacrosanct, if ever hunger, cold, or vigils I have
endured for you, time occasion spurs me that I claim reward
therefor. Now it behoves that Helicon pour forth for me, and
Urania aid me with her choir to put in verse things difficult
to think.


Cary:

     O ye thrice holy virgins! for your sakes
If e'er I suffer'd hunger, cold and watching,
Occasion calls on me to crave your bounty.
Now through my breast let Helicon his stream
Pour copious; and Urania with her choir
Arise to aid me: while the verse unfolds
Things that do almost mock the grasp of thought.


Temple Classics:

Now 'tis meet that Helicon for me stream forth
     and Urania aid me with her choir to set in verse
     things hard to conceive.