Do You Know What This Tool is For?

Patch reader Ruth Favro is asking for help. In a recent email from Patch, she wrote:

While unpacking a bag of items brought from my parents' house after they passed away, I found an old tool. I don't know what it is, and a search of the web didn't find anything. I wondered if one of the Patch readers might know what it is used for. I have attached three photos (top, bottom, and side views).

Do you know what this tool is and for what it is used?