‘And the second angel sounded and as it were a great mountain burning with fire was cast into the sea, and the third part of the sea became blood, and the third part of creatures which were in the sea died, those that had life, and the third part of the ships were destroyed.'
The second wind of heaven affects the sea (see Revelation 7:1). We are not told which sea is involved, (‘in Spirit' John could be anywhere) but the description may be of a meteor or asteroid crashing to earth producing great devastation and even changing the colour of the sea. Because it hits the sea its worst effects are avoided, but it still causes great devastation around it. The sea was always seen by the Israelites as an enemy, for they had few ports and little to do with it.
This is possibly not seen as being as widespread as the first disasters, for it affects only one sea, but it is deeper in intensity. God's judgments are sometimes widespread, and sometimes deeper in intensity. Whether such an event which meets all these criteria has specifically happened in history we may not be able to identify (so much of history is a blank to us), but we do know of devastation caused by meteors and other spatial objects, some of which have caused quite considerable devastation, and there are early records of such events. Once again ‘the third part' is apocalyptic language for great devastation.
Speaking of the 6th century AD Roger of Wendover (13th century AD) refers to a catastrophe that was exceedingly widespread, probably caused by the effects of a comet breaking up in space or an asteroid, as follows, ‘a comet in Gaul so vast that the whole sky seemed on fire. In the same year there dropped real blood from the clouds --- and a dreadful mortality ensued'. While almost certainly exaggerated the language has similarities with our passage. Such events have occurred, fortunately relatively rarely, throughout history, including in the twentieth century in, for example, Siberia.
John himself is thinking of a relatively short period for these activities, for he could not foresee the time that would elapse before Christ's Second Coming. These things were to ‘soon come about' and there can be no question but that things which could be interpreted as them were experienced in John's day. But God's perspective is different. He sees history as a whole. John is again saying that when such devastating things happen the Christian can be aware that it is not a sign that God has forgotten us. Rather He allows them in order to remind men of the even more devastating judgment to come.
On the other hand, the idea of ‘stars' (heavenly lights of one kind or another) falling from heaven and causing devastation are known in other apocalyptic literature (e.g. the Book of Enoch mentioned by Jude (Revelation 1:14)) and there they represent fallen angels. Indeed, the king of Babylon, who made great claims to deity was pictured as the Day-star, falling from heaven which suggests a similar background (Isaiah 14:12). It may thus be that that is the idea here, and that a powerful fallen angel is seen as carrying out what is written here.
If it is a fallen angel and not a specific natural catastrophe that is in mind it could again mean the angel does his work over a period of time. Fallen angels are a feature of Revelation and pictured as falling stars (Revelation 9:1-2; Revelation 12:4). (In Daniel 10 they are constantly at work throughout history). As these first four trumpets connect with the four angels at the corners of the earth (Revelation 7:1) this may well be so. But the deliberate avoiding of the word ‘star' suggests that in this case John may well be talking only of natural phenomena (in contrast with the third trumpet to follow).
The Third Trumpet Sounds.