The microscope body tube consists of a graduated drawtube that mounts to the main downtube. Objectives screw into one end of the tube, whereas the eyepiece drops into the drawtube end.
The top of the drawtube has this locating screw, presumably for a camera lucida.
W&H Seibert Objective No 2 and Unlabeled objective No 6.
Objective No 6 is higher magnification. It comes with a brass storage tube.
The eyepiece is labeled in script:
Carl Zeiss Jena
The eyepiece optics are of the Ramsden type.