ANGLE INDICATOR.....

I have an "Angle Indicator, made by McHugh Industries in Indianapolis Indiana" It has no date, no numbers and no other information on it at all.
I have sent emails and photos of it to Pudue Univ, Indiana Univ, Science and Industry Museum in Chicago, Marion CTY Library, and various tool museums all to no avail. NO ONE can tell me a single thing about this item. I know that in 1959 a Professor from Purdue wrote a paper called...
"Practical Applications of the McHugh Angle Indicator".
I have had this piece for 35/38 years now and have never seen another.
Does anyone know anything about it.....or what it's value is... HELP.
Thanks
Dick