I'll accept that as a reasonable take on Ovid's poem.
Do you agree with scifes that it wasn't until modern scientific gear was invented that the peoples of the world - ocean traders and fishermen and pearl divers and all - noticed that the depths of the ocean were dark, and the surface kind of wavy?
That they didn't, for example, look over the side of the boat and see the anchor being hoisted into the light?
I think if you read scifes response- he says in the end that to know the many levels of 'darkness' is a possibility of being known. But he is stressing the real 'miracle' of the internal waves.
I'm not saying that people did not know that ocean floor was dark- I only responded to your previous article because it clearly had nothing to do with the 'dark water' we are talking about.
But I'll still look at these quotes you provided: emphasis mine.
Orphic Hymn 23 to Nereus (trans. Taylor) (Greek hymns C3rd B.C. to 2nd A.D.) :
"To Nereus, Fumigation from Myrrh. O thou sho dost the roots of sea (pontos) keep in seats cerulian, Daimon of the deep, with fifty maidens [the Nereides] attending in thy train, fair virgin artists, glorying through the main:
the dark foundation of the rolling sea, and earth’s wide bounds belong, much-famed, to thee.
It may be that this is talking about the the ocean being dark at the 'foundation' (bottom?)... Although there is another way to look at it... That is to understand 'foundation of water'.
For example read here: The specific section "Tartarus, Cosmic Place" and also the next section.
http://www.maicar.com/GML/Underworld.html
Somethings to note in that article:
"Tartarus is the lowest
abyss beneath the earth where
all waters originate"
"Tartarus and the Underworld are the realm of Erebus, which is
pure Darkness."
"Tartarus is also a place of punishment."
"Tartarus is, they say, a gloomy"
Summary:
1. All water originate in Tartarus
2. Tartarus is associated with realm of Erebus which is 'pure darkness'.
3. Tartarus is associated with 'punishment', much like underworld
4. And Tartarus is a 'gloomy place'- and as most people would understand the 'underworld' and place of 'punishment' are pretty 'dark' places- at least when you try to imagine them they are pretty 'dark'.
In conclusion the 'foundation of water' is in a dark place of Tartarus- so for the quote you referred to to say that the the 'dark foundation of the rolling sea' would be in line with their cosmology and 'creation' of things. Seems more like reflecting what they believed about the 'underworld' then about the water itself.
As for the second quote- he is God of 'Sea'- If the foundation of 'all waters' is dark- then I'm sure he can get their.
Anyhow I think you're concentrating on the wrong issue.... I think, as noted by scifes in his response, the real question is about knowing the many layers of waves- both of your quotes do not give this detail.
Peace be unto you