From Scholar-Errant: A biography of Professor A.W. Bickerton, by R.M. Burdon, Pegasus Press, Christchurch, 1956, quoting an article by Bickerton in the Daily Mail, who was then apparently commenting on a plan by some Russian scientists to be launched to the moon from a large gun, a la Jules Verne's From the Earth to the Moon:
"How will you construct the gun that will stand this strain? ... you will enter the shell and detonate the explosive and start off at 7 miles a second. That is, you get a blow 50 times as hard as if struck by a Big Bertha shell. Clearly, you are flattened like a pancake. The bump is equal to a fall from a height of many thousands of miles .... This foolish idea of shooting at the moon is an example of the absurd length to which vicious specialisation will carry scientists working in thought-tight compartments .... all these errors could be easily avoided by correlative meetings of groups of different scientists investigating all kinds of cosmic problems. This is the work the Correlative Science Society, established by the Royal Botanic Society, has been attempting to do with most encouraging results."
From Basics of space flight, Ludwik Marian Celnikier, 1993, ISBN 2863321323, quoting "Discouraging Words", Spaceflight, 34, 225 (1992)
"This foolish idea of shooting at the moon is an example of the absurd length to which vicious specialisation will carry scientists working in thought-tight compartments .... For a projectile entirely to escape the gravitation of the Earth, it needs a velocity of 7 miles a second. The thermal energy of a gramme at this speed is 15180 calories .... The energy of our most violent explosive - nitroglycerine - is less than 1500 calories per grammer. Consequently, even had the explosive nothing to carry, it has only one tenth of the energy to escape the Earth ... hence the proposition appears to be basically unsound."
Quotes about Bickerton 
Bickerton's comments about space launch difficulty are often cited  as an egregious example of technological naysaying. However, Bickerton seems to have been addressing only the concept of projectile space launch into using conventional chemical explosives, a difficult proposition at best, and particularly for manned space travel, where his argument-from-stupendous-acceleration is accepted for obvious reasons. It is not clear whether he was commenting on the feasibility of rockets for this purpose, since none of the available quotes explain in detail what Bickerton meant by "the proposition".