It's interesting to note that these breakers in this little panel are bolted in to the line side, much like larger panelboards seen today. It also looks like there are a variety of other breakers (Westinghouse and G.E.) in there, in addition to Federal. i may be mistaken, but I believe the Federal breakers are in spaces 1,3,4 and 8 - I bought some of these old style Federal breakers some time ago on eBay to add to my collection of vintage equipment.
This is a very nice panel, and a nice addition to a collection...(you don't want to sell it, do ya