>Culp was the assignor, what does that mean?
A patent grants you a monopoly to make something or do something. You can licence other people to make or do that thing. Spencer was the inventor, he gave Culp the licence to make the thing patented. Doing this when the patent is filed is easy and convenient which is why we see the asignments in the patents, it can also be done after the fact, however when assigned that way, we can't see it in the patent documents...
Given that Spencer and Culp were both principals in Motor Spec Co, my guess would be that Spencer was the inventor, and Culp was the money man.
The assignment to a person instead of a company is a little odd, not not all that much so, it may just be it was financially convenient (for example not showing the patent as an asset on the company books) or it could be the two were think of starting their own business and not telling their employers....(stranger things have happened)
>How can I take this further
Google the names in google books, use advanced search, ***always*** check 'search free books only' , you don't care about them being free, but, to be out of copyright, they have to be old, and that's the fastest easiest way to restrict the date ; P
Also, backwards searching may yield something, look for patents assigned to Motor Spec co, and see who else is involved...Finding more inventors may lead to other companies that the inventors were dealing with...
The other thing is to try to find a list of distributors that carries stuff for Motor Spec, google books is a good place to start there. (Tip: search for 'automotive jobbers' rather than 'distributors' for that time period)
PS: To be fair here, I cheated a little finding the patent, I have stuff on my machine that is very hard to find with google patents in that date range, the OCR isn't very good for patents before the 40's...
