OBJECTIVES FOR COMPOUND MONOCULAR BAR LIMB MICROSCOPE

MAKER: ANDREW ROSS

c. 1843-54

The low power objective has only the initials R.D. in script. The other (later) 1/4 inch objective is signed in script A. Rosf, 1853. There is an adapter with mail threads to mate the objectives with the nosepiece. The nosepiece and the objectives all have female threads. Though the nosepiece threads are larger, they are not of the standard RMS form (about 0.8 inches (20.32 mm) in max diameter and 36 T.P.I. (0.706 mm) pitch) which was not adapted until 1858.