Possible Clues:

• Laugh let out by Church Army members
• Time learner in onerous task — and chuckle gleefully
• Short time in Lancashire town almost producing laugh
• Chuckle joyfully
• Express glee seeing officer caught up in boring duty
• Laugh when officer turns up, interrupting task
• Laugh as silly Hector grabs line
• ... stupid clothier I sacked for snigger
• Laugh and talk intermittently during task
• Noisy laugh