[Lynn]

Several reasons. The walls are five bricks thick, and they used varying sizes from two different plants. They would stagger bricks, laying some east west, and others north south. There were also areas where wood was mortared in place so they could hang things on the wall with nails.

Also, that large wall used to have windows and they were bricked up decades ago. I believe part of the wall was plastered at one time. You can see huge grinder marks left from an 8 to 10 inch grinder where the plaster was ground off.