Transcript:
So this, Jarvis, is the main Cathedral... This is... Hey!... You down there! Foolish laborer! That's no way to mold a moulded plinth! You don't... Aahh! Sir! Are you all right? I'm ok, Jarvis... Just some superficial damage to my flying buttress!
Apparently the Great Snow Castle includes not merely a chapel but a full-blown cathedral in Gothic style, with flying buttresses, which have saved Young Master’s butt.
(Jarvis didn’t really push him, did he?)