This is an antique microscope.
It is the Vertical Reading Microscope “VRM” manufactured by Ernst Leitz.
Serial No. 224263
Manufactured in 1923.
About VRM:
“VRM” stands for Vertical Reading Microscope.
It features a horizontally mounted optical tube on a vertical column and was designed to observe and record plant growth speed.
The tube height can be adjusted from 340–350 mm (13.4–13.8 in) using a sliding mechanism with rack and pinion.
Specifications:
Mechanical tube length: 163 mm (6.4 in)
Height: approx. 41–62 cm (16.1–24.4 in)
Width: 16.5 cm (6.5 in)
Depth: 16.5 cm (6.5 in)
Weight: 3.65 kg
Optics:
Eyepiece: 9×
Objective lenses: 3.2× (2 pieces)
Condition:
The microscope has been fully cleaned and remains in generally good condition.
All eyepieces and objective lenses are original Leitz products.
All mechanical functions operate smoothly.
Level Indicator (see photos):
A built-in level indicator is attached to the optical tube.
Engraving (see photos):
Because the VRM was produced for specialized purposes, production numbers were limited.
At the time, Leitz likely offered a custom engraving service.
This unit bears an engraving from the University of California.
Objective Lens Mounted on Tube (see photos):
This microscope supports long working distances.
Leitz provided three objective lenses for this model with working distances of 50 mm, 90 mm, and 480 mm.
The mounted objective lens has a 90 mm working distance.
Eyepiece (see photos):
Magnification: 5×
VRM-Specific Objective Lens (see photos):
Magnification: 2.4×
Working distance: 90 mm
Field of view: 10 mm
Sample Observation (see photos):
Plant tip
Observation magnification: 12×
Previous Owner (see photos):
This microscope was previously owned by Jochen, a collector based in Germany, shown together with his Leitz microscope collection.