| Quote #1
It did not appear to be the duty of these two men to know what was occurring at the center of the bridge; they merely blockaded the two ends of the foot planking that traversed it. (1.1)
Though the soldiers guard the execution, they don't seem to know what is going on. Maybe choosing to ignore the hanging makes their duty easier.
| Quote #2
As these thoughts, which have here to be set down in words, were flashed into the doomed man's brain rather than evolved from it the captain nodded to the sergeant. The sergeant stepped aside. (1.7)
Right before his death, Farquhar's thoughts are rapid and incoherent while his executioners act with precision and foresight. It's as if they're experience the same moment in completely different ways.
| Quote #3
These sensations were unaccompanied by thought. The intellectual part of his nature was already effaced; he had power only to feel, and feeling was torment. He was conscious of motion. (3.1)
After falling through the bridge, Farquhar becomes a completely physical being. Because he is in danger, his body takes over and his mind shuts down.