Sprague Vintage Glass Precision Resistor

[RDPipes]

I bought a lot of A&E parts, test equipment, miscellaneous, etc. about 20-25 years ago from a retired A&E technician dating into the 40's and earlier. Some of its gone now and some isn't. Digging around through whats left of it today and found this Glass Fuse? that I always wondered about. Anyone one know what its used for? It's 4000 ohm and still tests that. Its also marked with the maker Sprague and 40F 752E4025. I've seen my fair share of
fuses before but never a glass one this large. Can it possibly have anything to do with a phone system?
Is it a Cap or a Fuse, no voltage listed on it.

[RDPipes]

Gee! I thought at least one of you guys would have seen one of these before.

[TelePlay]

Maybe a 4,000 Ohm precision glass resistor?

Similar to this one 600 Ohm:

"Sprague Vintage Glass precision resistor 600 Ohm CSF-63071-F"

https://www.mercari.com/us/item/m14681536233

[RDPipes]

Maybe a 4,000 Ohm precision glass resistor?

Similar to this one 600 Ohm:

"Sprague Vintage Glass precision resistor 600 Ohm CSF-63071-F"

https://www.mercari.com/us/item/m14681536233

Bingo! That's a match sir, thank you!
Now to try and figure out what application is was used for, LOL!

[Etienne]

In 1908 Sprague associated with Thomson to produce trains for the Paris Métro. These trains remained in service until April 1983.
https://en.wikipedia.org/wiki/Sprague-Thomson
As far as I know, Sprague only built electric railway systems and elevators.
https://en.wikipedia.org/wiki/Frank_J._Sprague

[TelePlay]

Different Sprague.

[RDPipes]

Different Sprague.

Yes sir and they even made electric fans for a short time in the early part of 20th century if memory serves my right.