John Owen's poem: Umquam or numquam?

Question

I happened to see one of John Owen's poems, Horologium Vitae, which writes:

Latus ad occasum, umquam rediturus ad ortum,
Vivo hodie, moriar cras, here natus eram.

and it is translated poetically as: (I don't know who the translator is)

From East to West without return am I,
Born yesterday, live this day, next day die.

Umquam means ever, at any time, and it means never in a negative clause. Here no negation is implied so it seems to be at any time, which is the opposite of what the English version says.

I can think of the following cases:

1. Umquam can be negative itself, which I didn't find;
2. It is in fact numquam. I found no easily accessible reliable origin of his works so I can hardly check for it;
3. Owen made a mistake;
4. The English translation is wrong. If so, the meaning seems somewhat weird, however.

Which will be true for it?

Answer 1

It seems plausible that Latin version you quoted is corrupt and the original had numquam, in which case "numquam rediturus ad ortum" would refer to the fact that the sun's course in the sky above never goes from West to East, and would be correctly translated as "From East to West without return am I."

Here are three Google Book scans from less than a century after the original publication that show numquam (or equivalently, nunquam):

• Liber Tertius. 14. Horologium vitæ. Ad D. Joannem West, amicum suum.
  Latus ad Occasum, nunquam rediturus ad Ortũ,
  Vivo hodie, moriar cras, herè natus eram.

  Epigrammatum Joannis Owen, Cambrobrittani, Oxoniensis. Collegij B. Mariae (quod vulgò Novum vocant) nuper Socij, quae hactenus prodierunt Libri Decem. Leipzig: Thomas Schürer 1615. (Thanks to njuffa's comment!)

• Horologium Vitæ. Ad D. Ioannem West, amicum suum.
  Latus ad Occasum, nunquam rediturus ad Ortum:
  Vivo hodie, moriar cras, here natus eram.

  Epigrammatum Joan. Oweni, Cambrobritanni Oxoniensis editio postrema, correctissima & posthumis quibus adaucta, 1647, page 49)

• Latus ad Occasum, numquam rediturus ad ortum:
  Viuo hodie, moriar cras, heri natus eram.

  Simbolos selectos y parabolas historicas, Nicolas Caussin, 1677, page 382)

A version of the poem with "numquam" (also other differences) is found in this book from 1786:

De Horologio Vitæ.
Cursus ad occasum, numquam rediturus ad ortum:
Sum modo, cras moriar, natus heri fueram.

(Epigrammata Brevissima, partim de novo condita, partim ex variis poetis selecta, et in polonica translata, in quatuor libros divisa, page 92)

"Umquam" can't be negative by itself.

If the correct word is "umquam", I would interpret "umquam rediturus ad ortum" as meaning "ever going to return to the east", referring to the unseen ever-repeating return of the sun from the west to the east that occurs between sunset and sunrise. It is uncommon though for "umquam" to be used outside of a negative context.