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Cup Anemometer (Casella)


A wooden case with a latch and leather handle contains an anemometer consisting of two main components, a set of laminated documents, and a “University of Toronto Material Returned Report”.

Clamped in a wooden bracket inside the case is a component that is composed primarily of a translucent white plastic sphere. A short cable emerges from a mounting bracket at the top of this sphere. The end of the cable is held in a catch on the inside edge of the case This component is held in place with a latch.

A cable end is held in another catch inside the case.

A second component (a “cup rotor”) is held on a second bracket within the case. When the instrument is assembled for operation, this rests on a pointed spindle on the first component. 

The case also contains the following documents:

– Two laminated sheets Labelled “Sensitive Anemometer No. Standard  No. 1” and “Sensitive Anemometer No. Standard  No. 3” respectively. “Sensitive Anemometer No. Standard  No. 2” is printed on the reverse side of the first sheet. 
– A “University of Toronto Material Returned Report” dated Sept 25, 1969.

Accession Number: 2023.zoo.89

Alternative Name:

Sensitive Anemometer and Battery Charger

Primary Materials: Wood, Steel, Plastic


The first component has the following number embossed on a small silver label on the surface of the plastic sphere: “2411”

The “University of Toronto// Material Returned Report” includes the following information:
“Date: Sept 25, 1969”
“Returned to: Carlton Instruments Ltd.”
“Purchase Order No. D174841”
“T16110 Sensitive Anemometer// T16120 Five Figure Counter Unit”
“Received by: Mr. W. Smith”
“Returned by: Dr. J. B. Falls”

A paper tag tied to the leather handle of the case has the following handwritten number: “No. 2411”

Dimensions (cm):

Case: Height = 11, Width = 23.5, Length = 30.


This is a sensitive cup anemometer used to measure low speed airflows. It incorporates a cup rotor that is clamped to a spindle. Attached to the spindle is an opaque disk that is housed within the spherical enclosure. Half of the disk’s circumference is transparent. The rotation of this disk is measured based on alternate light and dark periods detected by a photocell.


The instrument itself is in excellent condition and may be unused. The surface of the wooden case is scratched, especially on the outer surface of the lid. There is a white corrosion on the connectors of the electrical cable and on three nuts attaching the cup elements of the cup rotor to the central spindle.

Associated Instruments:


C. F. Casella & Co. Ltd., Regent House, Britannia Walk, London, UK

Date of Manufacture: c. 1960s to 1970s


This artifact was acquired from Greg Mrychko of University of Toronto Facilities and Services on Friday, August 25th, 2023.

The “Material Returned Report” lists “Dr. J. B. Falls”. This is Dr. James Bruce Falls (b. 1923) of the University of Toronto Department of Zoology.

Additional Information and References:

The Science Museum Group catalogue lists an earlier model of this instrument dated 1950. (Entry archived on Friday, August 25th, 2023.)

Historical Notes:

  • Donated to UTSIC