Grandmother left this to me think its early 40s

From the base to top of glass its 54" the base is 11" the milk glass shade is 8". My grandmother left this too me dont know much about it was hoping maybe someone else did. All i can find is 4 pat# on it no other marks. They indicated its from late 30s to early 40s. If anyone knows anything about this lamp i would just love to learn a little about it so please anything helps thanks for your time.