The first type of all-bronze bearings from an early round-bed Drummond with separate upper and lower sections with the clearance adjustment by shims. Whilst the holding-down and adjustment screws are original the screw-in oil caps are not.

The front bearing of a later Round-bed Drummond with the unit formed as one piece with the clearance set by a slot and pinch bolt. The two large bolts should have a single slot across their tops - not hexagon sockets.
The large set-screw to the left bolts the cap down, assisted by two little screws mounted at each side of the right-hand bearing clearance adjuster bolt.

Another view of the front bearing - showing evidence of having been clamped in a rough-jawed vice at some time.