Fire of Isengard ?

[The Might]

I had the idea for this thread today as I was reading through LOTR...
It was the passage where the battle at Helm's Deep is described:

Even as they spoke there came a blare of trumpets. Then there was a crash and a flash of flame and smoke. The waters of the Deeping stream poured out hissing and foaming: they were choked no longer, a gaping hole was blasted in the wall. A host of dark shapes poured in.
'Devilry of Saruman!' cried Aragorn. 'they have crept in the culvert again, while we talked, and they have lit the fire of Orthance beneath our feet.

After I read this, I however remembered of something I read in The Hobbit, a description of the goblins living in the Misty Mountains:

Now goblins are cruel, wicked, and bad-hearted. They make no beautiful things, but they make many clever ones. They can tunnel and mine as well as any but the most skilled dwarves, when they take the trouble, though they are usually untidy and dirty. Hammers, axes, swords, daggers, pickaxes, tongs, and also instruments of torture, they make very well, or get other people to make to their design, prisoners and slaves that have to work till they die for want of air and light. It is not unlikely that they invented some of the machines that have since troubled the world, especially the ingenious devices for killing large numbers of people at once, for wheels and engines and explosions always delighted them, and also not working with their own hands more than they could help; but in those days and those wild parts they had not advanced (as it is called) so far.

As it is mentioned here, the Orcs had not reached such an advanced level in industry and science in the wild, however under Saruman's guidance at Isengard it might have been a very different story - in this case the Orcs might have learned how to use explosives, which were used for the "bomb" at Helm's Deep, and also for the machines in the caverns of Isengard.

Suddenly up came fires and foul fumes: the vents and shafts all over the plain began to spout and belch. Several of the Ents got scorched and blistered. One of them, Beechbone I think he was called, a very tall and handsome Ent, got caught in a spray of some liquid fire and burned like a torch: a horrible sight.

As we see some of these machines also used similar substances, perhaps also made by the Orcs.

[Boromir88]

Ahh the Fire of Orthanc...always an interesting topic.

I think it's fair to say that Saruman had improved upon the 'explosives' to use for his own destructive purposes. You can't talk about Saruman's explosives without mentioning Gandalf's Fireworks, as both work with the same elements yet one uses them for entertainment the other for destruction. I think both Gandalf and Saruman use magic and some sort of explosive (probably gunpowder) to create their 'devices.'

As Gandalf states he simply 'can't just melt snow'. There has to be something there for Gandalf to work with. However, I do think Gandalf uses his magical abilities to enhance the fireworks. I work for a fireworks company and we are struggling with making smiley face designs. Gandalf has his fireworks explode into a mountain and a dragon...I'd say there has to be something magical about it.

Now onto Saruman's 'Fire of Orthanc' where I believe he also used magic to enhance the explosives he used at Helm's Deep:

The basic motive for magia - quite apart from any philosophic consideration of how it would work - is immediacy: speed, reduction of labour, and reduction also to a minimum (or vanishing point) of the gap in time between the idea or desire and the result or effect.~Letter 155

Magia is used to increase speed, efficiency, and reduce the amount of labor. Saruman wanted to break down the defenses of Helm's Deep as quick as was possible. And using his magic would increase the potency of the explosives and do just that.

[The Might]

And as we are talking about this topic I guess it might be good to provide some quotes that also mention Saruman's interest in such things:

...but Curunír went most among Men, and he was subtle in speech and skilled in all the devices of smith-craft.

Also, it makes sense as well since he was a Maiar of Aule:

Curumo, who was chosen by Aule

It does make sense that he enhanced the explosives, but I believe the Orcs were at the time no strangers to such things either, and as suggested in the quote from The Hobbit they took great delight in using such a weapon.

[Mänwe]

Originally posted by Boromir88

“Now onto Saruman's 'Fire of Orthanc' where I believe he also used magic to enhance the explosives he used at Helm's Deep.”

An interesting point, though I was wondering if I might be allowed to take another angle on this, and say, no, he did not use magic. In a more practical sense the culvert in which they placed the crude device was small, made more so by that fact that the defenders of Helm’s Deep had blocked it so that the orcs were unable to come through.

“They gathered such small boulders and broken stones as they could find to hand, and under Gimli's direction the Westfold-men blocked up the inner end of the culvert, until only a narrow outlet remained. Then the Deeping-stream, swollen by the rain, churned and fretted in its choked path, and spread slowly in cold pools from cliff to cliff.” – (Chapter 7, Helm’s Deep)

This coupled with the fact that the culvert is by design already a confined space, would have served to contain the explosion, so that the force was not dissipated to the sides wasting the explosive energy, but being contained would have been amplified, thus generating such a destructive force as was seen; blowing the subsequent breach in the Deeping Wall.

Also concerning your quotation of the letter, I have been slightly confused by the topic of magia and goeteia. And perhaps I have misunderstood what you mean, you say that Saruman uses magic to enhance the explosion, then go on to quote magia;

“The basic motive for magia - quite apart from any philosophic consideration of how it would work - is immediacy: speed, reduction of labour, and reduction also to a minimum (or vanishing point) of the gap in time between the idea or desire and the result or effect.” – (Letter #155)

But isn’t the magia here the actual explosive device itself, and is therefore not magic, nor is there any magic enhancing it; this enhancement being magia, for it is the gunpowder as you say, which has been to;

Originally posted by Boromir88

“…break down the defenses of Helm's Deep as quick as was possible.”

[The Might]

Good post Manwe
Indeed the fact that this "bomb" had been placed in a narrow place would have increased its effect much more, but still, it could be that both these ideas are correct. Saruman might have enhanced it with his magic, and had perhaps planned that it should be set in a narrow place. Perhaps the Orcs entering the Deep that way were just used to make sure the defenders would block the culvert.
Now, I wouldn't exactly call the device magic...it was just a proof of more advanced technological invention in a not so developed world. I am sure that the indians thought the weapons of the conquistadors were using some kind of magic as well, but I believe we must differenciate between magic and superior technology. We see Saruman was definitely interested in enhancing and inventing things, we see proof for this in Isengard and in the Shire.