Antique School Desk - who is the Manufacturer?

I acquired a child's old school desk and I'm trying to find the manufacturer of it. It has a cast inscription, "Pat. Sept 18, 1888" that is shown in the scroll frame photo, but is difficult to see. I searched for patents for that date and I only found Elijah Haney. I did research on Haney and found a picture of their cast label that was used on the desks after 1889. I can't find their cast inscription that was used prior to 1889.

I appreciate any feedback that I receive. Still searching...