Miller opened the scoring before Briggs, Ciara Griffin and Liz Burke all ran over in a first-half storm that blew the Scots away.
Jenny Maxwell's individual score gave Scotland a glimmer of hope just before half-time, but it was swiftly snuffed out after the break as Briggs grabbed a double and Miller her hat-trick before Sophie Spence's and Rhona Lloyd traded late tries.
Shade Munro's side have steadily improved throughout the Women's Six Nations, but they were soundly beaten today by Tom Tierney's charges and will finish bottom for the sixth consecutive year.
Munro's side's ill-discipline cost them points almost immediately, the Irish pinning them deep inside their 22 with the boot before the pressure eventually told and Miller flopped over from the back of a tightly packed maul. Briggs converted.
Ireland offered little respite to the Scots and with Sene Naoupu bossing proceedings in attack and Claire Molloy a constant source of go-forward, they extended their lead after eight minutes.
Naoupu took the ball at pace, fixed two defenders before moving the ball to Briggs, who put Liz Burke over in the corner for her first score, but Briggs was off-target with the conversion.
Ciara Griffin crossed moments later to heap further misery on the visitors as Ireland's first-half blitz continued, giving them a 17-0 lead after 15 minutes, which Briggs compounded with a penalty on 27 minutes.
Another moment of excellence from Briggs put Ireland a long way out of sight, the full-back's clever chip-kick put her beyond the defence and she dived over for Ireland's fourth try.
Scotland struck back through Maxwell just before the break, the scrum-half showed good pace and vision to elude the Irish defence and race over before hooker Lana Skeldon added the extras to leave Munro's women 25-7 behind at half-time.
Molloy's exceptional shift continued after the break, the openside consistently broke the gain-line and just two minutes into the half she created the momentum for Miller to grab a brace. Briggs was off target with the conversion.
A big Briggs hand-off was the finishing touch to some excellent Irish play with just over half an hour left as Ireland's captain bumped over for her second of the afternoon, but again missed the conversion.
Scotland were reduced to 13 players after continued indiscretions and Naoupu turned provider once again with 20 minutes left - a wide fizzing pass sending Miller over to complete her hat-trick. Briggs' inaccuracy with the boot continued to leave the score at 40-7.
Replacement Spence struck the final blow for Tierney's women before Lloyd crossed for a consolation score on the stroke of full-time.
England defeated New Zealand 49-46 to level up the three-match Series at 1-1 heading into the deciding match on Wednesday morning.
Sloane Stephens advanced to her first Grand Slam final at the US Open on Thursday night