[Jaysun]

Here's the pistol in question next to one of my Iver Johnsons. While it isn't the exact same model as the one that you pictured, the frames and cylinders are shaped the same. Maybe this will help.

[Squantos]

As ya state the 100 year old home etc and the fact one is a top break makes me think your smaller revolver is the IJ or an IJ clone from around the turn of the century......The top break IJ has all the "signatures " to suggest Iver Johnson or an H&R clone of it.....tomorrow.

Stay safe !

[Swordmaker]

Here's the pistol in question next to one of my Iver Johnsons. While it isn't the exact same model as the one that you pictured, the frames and cylinders are shaped the same. Maybe this will help

Iver Johnson made both top-break and solid frame .22 revolvers. Your top-break model is not comparable. What caliber is your top-break?