The idea of gas engines was by no means new, but this was the first time that a really serious effort had been made to put them on the market. They were received with interest rather than enthusiasm and I do not recall any one who thought that the internal combustion engine could ever have more than a limited use. All the wise people demonstrated conclusively that the engine could not compete with steam. They never thought that it might carve out a career for itself. That is the way with wise people--they are so wise and practical that they always know to a dot just why something cannot be done; they always know the limitation...
Recently, a friend was telling me that DSLR cameras will never be supplanted by cameraphones. As of 2010, it seems a silly proposition. But that's seeing camera technology as they are now, not what they will be.
I don't think DSLRs will ever go away, like the radio never went away. But I don't think it's infeasible that cameraphones will get better and better so that for many DSLR users now, it would get 'good enough'.
I sent him the post I wrote on this subject. But I don't think he read it.