The Bees achieved their fourth successive win, despite conceding a second-minute penalty and finishing the game with ten men after Dean Sinclair's late dismissal for an ill-judged challenge on Richard Baker.
At the end of a week in which the FA confirmed their expulsion from the FA Cup for fielding ineligible Hartlepool loanee Stephen Turnbull in the second-round win at Chester, Bury might have arrived in Hertfordshire feeling sorry for themselves. Not a bit of it.
Despite suffering an additional setback when top-scorer Andy Bishop was ruled out by a thigh strain ahead of kick-off, the visitors were quick to grasp the nettle, Baker converting a second-minute penalty after Matthew Blinkhorn was brought down in the area by Ismail Yakubu.
But with belief coursing through the veins of Paul Fairclough's men after their impressive recent run, it was never going to be easy for the Shakers.
Four minutes later the visitors' dream start turned into a nightmare, the Bees breaking quickly down the inside-left channel before Bailey stole into the area to nod home Richard Graham's far-post cross for his fourth goal of the season.
The frenetic early pace continued, and when the lights went out on one side of the ground before starting to flicker on and off, the pitch began to resemble a dance floor.
Birchall took the hint, and it was not long before the Barnet marksman was confidently strutting his stuff. With 18 minutes gone Graham's long-range shot was deflected into his path, and the Mansfield Town loanee was quick to apply his nifty footwork, gathering the ball calmly before turning to slam home from all of four yards.
Worsening conditions made the second period difficult for both teams, but the pick of the chances again went to Barnet. Jason Puncheon and Barry Cogan spurning presentable opportunities to extend the home side's lead until Sinclair's dismissal set up a nervous finale.