The Two Towers by J.R.R Tolkien (Harper Collins 1991, 2007) pp.623-635
The night that Merry and Pippin spend in Wellinghall is the first since they escaped from the Orcs and the first that they have had in a home, a place of safety, since leaving Lothlórien, and so they sleep long and refreshingly.
Treebeard takes them to Entmoot, the council in which the Ents will deliberate what course of action they must take.
“Deciding what to do does not take Ents as long as going over all the facts and events that they have to make up their minds about”, Treebeard says to the hobbits, and he estimates that this will take a couple of days or so. He sends Merry and Pippin off with a younger Ent called Bregalad or Quickbeam who has already made up his mind about what should be done and the hobbits spend those days in his company as the Moot continues.
It is on the third day, a bleak and windy day, in the afternoon, that all falls silent and then with a great crash and the quivering and bending of the trees that the Ents march towards them.
“We come, we come with roll of drum: ta-runda runda runda rom!”
The Ents are marching to Isengard and to war.
It is through Merry that we learn something about Isengard. Merry is the organiser of the four hobbits, the original company of the Ring that left the Shire some months before these events. He organised the purchase of Crickhollow in Buckland, and, as the real reason why Frodo is leaving Hobbiton became clear it is Merry who made secret preparation for leaving the Shire. He is rather proud that while Pippin spent his days in Rivendell idling away the time he tried to find out as much as he could about what might lay ahead.
“Isengard is a sort of ring of rocks or hills, I think, with a flat space inside and an island or pillar of rock in the middle, called Orthanc. Saruman has a tower on it. There is a gate, perhaps more than one, in the encircling wall, and I believe there is a stream running through it; it comes out of the mountains, and flows on across the Gap of Rohan.”
Orthanc is not Saruman’s work but much older having been built by the Númenorians in the days of Elendil. It was a sign of their decline that during the first part of the Third Age it became a lawless place far from the authority of Minas Tirith and a thorn in the side of the new kingdom of the Rohirrim who had settled in the plains of Calenardhon that lay between the southern end of the Misty Mountains to the north and the mountains of Gondor to the south. So it was that when Saruman took possession of Isengard in 2759 of the Third Age both the Steward of Gondor and the King of Rohan welcomed him gladly seeing him as a valuable ally who would watch over the strategically vital Gap of Rohan.
It would seem that Saruman was able to keep his true intentions secret right until the moment he took Gandalf prisoner during the time in which Frodo was making preparations to leave first Hobbiton and then the Shire, although Treebeard seems to have been aware of these intentions for some time and the presence of orcs in Isengard. Even after going to war with Rohan Saruman was able to keep Théoden from making a strong response through the efforts of Grima Wormtongue his chief counsellor who was able to convince Théoden that Saruman’s true wish was for peace.
It is with the arrival of Merry and Pippin in their pure, gentle and artless simplicity that the dam finally bursts and the slowly simmering anger of the Ents finally comes pouring out of Fangorn and down to Isengard. It is as if Nature herself finally rises up against the powers that would destroy her. But even as the Ents march upon Isengard and upon Saruman Treebeard is aware that Nature may fail, that it is “likely enough that we are going to our doom: the last march of the Ents”. But, he adds, “if we stayed at home and did nothing, doom would find us anyway, sooner or later”. The possibility that disenchanted Nature could yet reawaken and rise against a world of “metal and wheels” was something that the Inklings pondered both through the character of Merlin in C.S Lewis’s That Hideous Strength and through Treebeard in The Lord of the Rings. Tolkien allows such a revolt to take place but recognises the heartbreaking fragility of Nature that may yet fall before the walls of Isengard and before technology.