Basically, all of that is speculation, though.
We don't know what the emissions of the thing contained, besides the whalesong. We don't know if the destructive effect was ancillary, incidental or deliberate. We don't know if the thing communicated with whales or not, and even whether it cared about the absence of the whales, as opposed to apparently caring about their presence.
Might be it wasn't whalesong to begin with: could be the aliens' own thing that the whales, after repeated exposure (say, when the cylinder thing last visited Earth in late May 1876), had learned to mimic without comprehending, even passing the skill to their calves (although this would not necessarily be a requirement in the 1876 visitation case - George and Gracie both might have been there to witness it).
Ultimately, we know less about the thing than the heroes do (say, where it came from and where it went), and that's already next to nothing. We may speculate that it had some designs on Earth since we saw it boil Earth's oceans, but perhaps Earth was just #321 in a row that we never got to see. We may speculate it stopped the boiling when it heard its own engine noises reflected from the seas; saw it was quaint biological lifeforms generating those; was amused; and decided to postpone the boiling task till its superiors really pressed the case.
Or then the alien visitor indeed was a whaleherd of some sort, monitoring the progress of a twenty-million-year plan of populating the planet with cetaceans, and being really embarrassed about having fallen asleep on the wheel and therefore just mumbling a few phrases and then departing when finding out that only two of the herd survived. It might be back, or might be demoted or executed for its failure and the project either abandoned, or then started anew a bit later on. It's just that we don't know, and the heroes probably don't, either. Although they'd be motivated to find out, and I don't see why they couldn't. It's not as if the alien was superfast or superstealthy, say. Just chase it!
Timo Saloniemi
We don't know what the emissions of the thing contained, besides the whalesong. We don't know if the destructive effect was ancillary, incidental or deliberate. We don't know if the thing communicated with whales or not, and even whether it cared about the absence of the whales, as opposed to apparently caring about their presence.
Might be it wasn't whalesong to begin with: could be the aliens' own thing that the whales, after repeated exposure (say, when the cylinder thing last visited Earth in late May 1876), had learned to mimic without comprehending, even passing the skill to their calves (although this would not necessarily be a requirement in the 1876 visitation case - George and Gracie both might have been there to witness it).
Ultimately, we know less about the thing than the heroes do (say, where it came from and where it went), and that's already next to nothing. We may speculate that it had some designs on Earth since we saw it boil Earth's oceans, but perhaps Earth was just #321 in a row that we never got to see. We may speculate it stopped the boiling when it heard its own engine noises reflected from the seas; saw it was quaint biological lifeforms generating those; was amused; and decided to postpone the boiling task till its superiors really pressed the case.
Or then the alien visitor indeed was a whaleherd of some sort, monitoring the progress of a twenty-million-year plan of populating the planet with cetaceans, and being really embarrassed about having fallen asleep on the wheel and therefore just mumbling a few phrases and then departing when finding out that only two of the herd survived. It might be back, or might be demoted or executed for its failure and the project either abandoned, or then started anew a bit later on. It's just that we don't know, and the heroes probably don't, either. Although they'd be motivated to find out, and I don't see why they couldn't. It's not as if the alien was superfast or superstealthy, say. Just chase it!
Timo Saloniemi
