Muddling with Pliny's Dolphin

I’ve been reading some of Pliny the Younger’s letters. Lord, he can be a snob. But the historical and anthropological interest makes up for it.

Anyway, I have a grammar problem which I’d be grateful for any insight readers might have. In letter 9.33, Pliny writes about the story of a very friendly dolphin in a tidal pool somewhere in North Africa. The dolphin makes friends with a local boy, and whilst the boy is still tentative, Pliny describes the following:

Delphinus, quasi invitet et revocet, exsilit mergitur, variosque orbes implicat expeditque.

Now I translated this like this: “As if inviting him [the boy] or calling him back [out into the pool], the dolphin jumps out of the water and dives back in; it swims round in a circle after circle and breaks off from them.” Translations I consulted, however, seem indicate that the dolphin didn’t swim in circles but rather “curl itself into different shapes and then uncurl itself.”

I’ve checked in the dictionary (OLD) for implico and expedio, though I haven’t come to a firm conclusion as to whether my reading is acceptable or not. Is the text ambiguous, or am I wrong? (Or right?!)

If anyone can shed light on how dolphins do behave, and whether they do wrap themselves into balls, I’d be very interested to know that too!

I have no idea what actual dolphins do but I can see nothing in the Latin which explicitly talks about swimming. variosque orbes is the direct object of the verbs implicat and expedit and the Dolphin is the subject. OLD gives (1b.) “disentangle” as a meaning of expedio and implico has the meaning “1. To fold or twine (a single object) about
itself.”

So I would have thought “The Dolphin…folding itself in various/different circles and (then) disentangling (itself)”. Or coiling and uncoiling as the Loeb puts it.

In the first part of the sentence et is and rather than or. …as if inviting him and calling him back.

Hmm, yes, I saw that OLD has this passage down as you describe under both expedio and implico. I don’t find the classification very satisfying, I suppose. Does OLD’s “to fold or twine (a single object) about itself” fit the translations that indicate orbes are the shapes the dolphin is wrapping itself into? It seems to torture the definition a little, and the other examples given in the OLD section are not immediately very illuminating.

And there’s nothing explicit about swimming - you’re quite right. I used “swim” to indicate that I took the action to involve movement - that the dolphin is going in circles.

In checking this over again, I note that Lewis & Short quotes Vergil’s description of Turnus with very similar vocabulary:
Ergo amens diversa fuga petit aequora Turnus
et nunc huc, inde huc incertos implicat orbes
12.742-3
Here Turnus is clearly moving about.

Thank you for weighing in. (And fixing my sloppy “or”.)