Originally Posted by Vicki W
When I first looked, my thought was inkwell, after I have read the comments. It seems that most agree. Two things could have happened, the model could have been multiple purpose, serving as a ladies "office' or a desk could have been repurposed for the machine.
I'm going to guess the desk is a sewing desk. The machine's knee control can be seen in the knee hole. A talented carpenter could set up a machine in a regular desk, however, I'm guessing not.