Thick Gingerbread (1861)

Revisiting a perennial favorite from Mrs. Beeton (and, if I recall correctly, the first period receipt I ever tried to follow). 

1760. Thick Gingerbread from The Book of Household Management (1861)
Also here, with better search functionality, but fewer illustrations.

Rarely having treacle on hand, I've often substituted molasses, to good effect, with slight variations of color/flavor.  One iteration of this receipt will fit an 8 x 12 baking pan, or generously fill a loaf pan-- carefully check that the center is baked when using a loaf pan; the sides may be well done by time the center is cooked.

Thick gingerbread.

For reference, 1.5 lbs of all-purpose flour is about 5 cups, and 1 lb of molasses or treacle is about 1.3 cups; 1/4 pound brown sugar is between a generous half cup (packed) and 7/8 cups (loose).