I just purchased a house built in 1899 which has framing for transoms over the interior doors. I want to open the transoms but when I removed the wood covering one of the transom openings I found plaster there just like the walls, instead of an opening or glass. Do you think the openings were plastered closed after the windows were removed or were they never working transoms but rather decorative woodwork instead? I am concerned that if I try to remove the existing plaster in the transom openings I could damage the surrounding walls if it was done when the house was built. Thanks