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DLSPH Occupational Health

A lockable wooden box contains a metal optical instrument mounted on a wooden base. The lock has a key in it.

The instrument is partly painted black, partly polished metal. The instrument is attached to a wooden base plate at three points using hinged wingnuts.

A tube-like section, ending in a polished metal handle, protrudes horizontally from the base of the instrument and ends in a circular polished metal handle. This section is supported by an elevated section of the wooden base. Two cylindrical vertical elements, one taller than the other, protrude vertically from the instrument. The taller section ends in an optical ocular element.

The box also includes several other items:
– Another box of round glass pates with a ground glass centre.
– A tube of Canada Balsam adhesive.
– A small grey mechanical counter manufactured by Veeder-Root inc of Hartford, Connecticut.
– A small black microscope illuminator manufactured by Bausch & Lomb Optical co. of Rochester, NY.

Accession Number: 2016.phlt.1.104.1-6

Alternative Name:

No WB4400 Bausch & Lomb Dust Counter

Primary Materials: Metal, Wood


The top of the box has a green label of embossed tape that reads “ENVIRONMENTAL HYGIENE”.

Dimensions (cm):

Box: Length = 23.4, Width = 16.1, Height = 27.8


This instrument is used to measure particulate matter in a work environment.


Very Good: The wooden box and instrument base are slightly marked and abraded. Parts of the counter are slightly rusty.

Associated Instruments:

2016.phlt.1.127.1-2 is the same model of instrument.

Manufacturer: Bausch & Lomb co, USA.

Date of Manufacture:


Additional Information and References:

Historical Notes: