[SamwiseGamgee]

I agree with an earlier observation that it seems to be the evil powers in ME who have developed further technology- the 'bomb' of Saruman, the crossbows of the orcs and the mass forging of swords in contrast to the very individual approach taken to swords, bows and axes etc by men, elves and dwarves. I think it's a fairly well known fact that Tolkien himself despised the whole industrialisation process (it's in Letters somewhere and also is fairly apparent from the way Tolkien writes when the hobbits return to the Shire and everything has changed), and thus in his own mind when writing surely it would have been in his mind to keep the forces of good away from such widespread industrial revolutions.