Equatorial dials

Henry Moore, IBM (La Hulpe, Belgium) and Adler (Chicago, USA)

This impressive bronze dial, made by the famous sculptor Henry Moore, is located on the campus of the IBM Training Center in La Hulpe, some 15 km (10 ml) south-east of Brussels (Belgium). It measures 3.6 meter (12 ft) in diameter. The two arches are triangular in cross-section, the equatorial arch having its flat side looking inward, the vertical arch its sharp edge. A subtle detail, which yet clearly distinguishes the artist designer from the engineer. Superb!!

The flat side is provided with the time scale, from 6 to 6 (18) hr local time, divided into 5-minute intervals. The pole-style is 24 mm (almost 1 inch) across, so that it spans 0.76° as seen from the time scale. That is sufficient to cover the 0.5° of the solar disk and to yield a clear-cut shadow, as the picture below shows.

The dial was commissioned to Moore by Sir Gavin Astor, owner of the London Times, and has been standing in front of the newspaper's headquarters. The above photo, from the cover of the book Sundials by Frank Cousins (John Baker, 1969), shows it there. When the company moved outof the city, the building was torn down. I have not yet been able to trace how and when the dial ended up in Belgium.
The latitude difference between London and Brussels is less than a degree, so the dial should function well in its new location.

In his book, Cousins relates the history of this design (p. 141). The architects Llewelyn-Davies and John Weeks designed the newspaper's new headquarters, and in collaboration with dr. Ward also the sundial. Moore refined the design and made a model of ca. 50 cm (20") diameter. Cousin's book also has a picture of it (p. 142). Twenty-one copies of this model were cast. One copy is in the Henry Moore Museum in Much Hadham (some 30 km -20 ml- north of London).

Original location: 51.5° N, 0.1° W
Present location: 50.7° N, 4.5° E
Design: Henry Moore
Inauguration: November 1967

Moore sold his own copy of the dial to the Adler Planetarium in Chicago in 1980. It was cast only after its new location was known, so that the position of the foot could be adapted to the latitude of Chicago, which is about 10° south of London. Placed at the shore of Lake Michigan, it makes for a splended view.
I found this pretty picture on the website of Andreas Hänel.

Location: 41.8° N, 87.6° W
Design: Henry Moore
Inauguration: May 1980

I am indebted to Ms. Anita Feldman Bennet of the Henry Moore Foundation and Dr. Bruce Stephenson of the Adler Planetarium for the information they provided.

A case of blunt of plagiarism can be seen in the June, 2002 issue of the NASS Compendium.

According to the explanation to this photo, the dial stands in the harbor of Grand Haven, Michigan (USA) and is about 7 feet high. The inscription reads: "Donated and Crafted by the Employees of Grand Haven Brass Foundry 1985". The hour ring has markings from 8 am to 7 pm, with the meridian at 1:45 pm (accounting for DST and Grand Haven’s longitude).

The dial thus is about half the size of the Henry Moore original, reads civil instead of local time, and has a less elegant foot.