Possible Clues:

• I am certain
• This writer's sure to make a prediction of personal restriction
• Laid up in bed, ship's officer will lose heart for sure
• No doubt hollow breeze blocks not properly secured?
• Certainly how Houdini would describe first stage of his routine
• No doubt they're going to tie me up
• Fickle, bold, nubile - I am sure that's true
• Believe me, Prometheus might have uttered this, anticipating his punishment