Please help to identify ( The Treadwell Collection ) on this photo , Who is Treadwell ?

I believe it is probably from the collection of Dr. T. K. Treadwell (Full name was Thurman Kelso Treadwell). He was a very well-known expert on stereoview photographs and had a large collection. He lived from 1920-2003. Here is a brief tribute to him and to his expertise.
https://saddyauctions.com/tk-treadwell-tribute.html

 

He died in 2003. Wouldn't he be a little too young? I did find a reference to a stereoscope publisher in Boston named the Treadwell Collection but doesn't seem quite right.

Debora

 

He marked the views he had in his collection, Like people who put bookplates with their name in books they own. They have ended up scattered all over the place by now. I've bought random collections of views and found cards marked with his name.

 

Here's a view I have that he took the time to write a description for. Notice the same numbering system at the bottom.

 

Ah! Dos dedos, as they say in Spanish. That makes sense. Thanks for de-confusing me.

Debora

 

I have photos from other people's collections that they marked similarly. Don't think I have any from Treadwell's.