1887 magazine article concludes airplanes to be physically impossible

Something to keep in mind when reading articles about how warp drive is impossible; let's not forget that in the late 19th century there was also a great divergence of opinion over whether flying machines were possible either. An article from a professor in Popular Science Monthly in 1887 confidently concludes that flying machines just can't exist.

THE PROBLEM OF A FLYING MACHINE. -- We must admit that a bird is an incomparable model of a flying machine. No machine that we may hope to devise, for the same weight of machine, fuel, and directing brain, is half so effective. An yet, this machine, thus perfected through infinite ages by a ruthless process of natural selection, reaches its limit of weight at about fifty pounds! I said, "weight of machine, fuel, and directing brain." Here is another prodigious advantage of the natural over the artificial machine. The flying animal is its own engineer, the flying machine must carry its engineer. The directing engineer in the former (the brain) is perhaps an ounce, in the latter it is one hundred and fifty pounds. The limit of the flying animal is fifty pounds. The smallest possible weight of a flying machine, with its necessary fuel and engineer, even without freight or passengers, could not be less than three or four hundred pounds.

Now, to complete the argument, put these three indisputable facts together: 1. There is a low limit of weight, certainly not much beyond fifty pounds, beyond which it is impossible for an animal to fly. Nature has reached this limit, and with her utmost effort has failed to pass it. 2. The animal machine is far more effective than any we may hope to make; therefore the limit of the weight of a successful flying machine can not be more than fifty pounds. 3. The weight of any machine constructed for flying, including fuel and engineer, can not be less than three or four hundred pounds. Is it not demonstrated that a true flying machine, self-raising, self-sustaining, self-propelling, is physically impossible? -- Prof. Joseph Le Conte, Popular Science Monthly.

Without a single example of a mechanical flying machine to contradict this it actually looks like a pretty solid argument at the time. The counter-argument could be made that eventually humans would find ways to become more efficient than animals, but at the time that would sound similar to the idea of FLT travel today - sure it may be theoretically possible, but when will we reach that level of sophistication, if ever?

This is not to say that any theory on new propulsion is therefore possible, but it's good to remember this example of some pretty impressive scientific minds having reached the conclusion that even simple mechanical flight was a sheer impossibility akin to perpetual motion. Those that have decided today that propulsions x, y or z are sheer impossibilities would be well served by taking a second look at their calculations to make sure that nothing has been left out in order to not become another Professor Joseph Le Conte.