I presume you are led to this by the winged globe design on the Studies and the pyramid monument in the Society's cemetery. Russell and many other, including Lutherans, Presbyterians, Baptists, famous clergymen some of them, were persuaded that the Great Pyramid was built by Melchizedek. Nonsense of course, though still believed. But in the Russell era it was a widely spread belief. Russell accepted it along with many others.
One should note that Russell had no hand in the pyramid monument. It's not his grave marker. That's a headstone nearby. It was designed by a Bible Student and built after Russell's death. It was not meant to connect Bible Students or Russell to the Masons. That claim is unsupported by facts. It was meant to connect to Russell era belief that the capstone on the pyramid was a picture in stone of Jesus, "the head of the corner."
You will find more in Separate Identity, vol. 1 and on the blog to which Mom contributed before her death.
https://truthhistory.blogspot.com/
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