This was the "falling" which was taken by many as an indubitable sign of the divine power.
Susannah had seen it often under Smith's preaching.

She waited with indifference until he was lifted up.
Then the sea of faces around her, the powerful voice of the preacher resounding above, passed away like a dream, and were exchanged for a small room and a dim light, where two or three people were gathered round the form of the insensible man.

She escaped unnoticed through a private door into the fields, where the March wind eddied in the black night..