Early Calculator Unearthed in Observatory Archives


Front of the calculator

A rare early financial computing device has been unearthed among the archives of the Armagh Observatory by Thirza Mulder, Archivist for the Armagh Public Library. The British Calculator, Model C, was part of the personal collection of Joseph Alfred Hardcastle, who had been appointed Director of the Observatory in 1916 but was taken ill and sadly died on his way to take up residence in Armagh. The item, which appears to be for use in the addition of pounds, shillings and pence, formed part of the Hardcastle material auctioned by the firm of George Mealy and Sons Ltd. in December 2003.

Hardcastle was a grandson of Sir John Herschel, and a great-grandson of Sir William Herschel. He was a son of Maria Sophia, Sir John Herschel’s third daughter. Maria Sophia had married Henry Hardcastle, the son of Joseph Alfred Hardcastle M.P., in 1865. Joseph Alfred Jr. was born in 1868 and was educated at Harrow being awarded the Neeld Gold Medal for mathematics in 1886. He went up to Cambridge University in 1887, but owing to family circumstances he left Cambridge the following year to pursue a business career.


Reverse of the calculator

In 1890, he began suffering from the health problems that were to last for the rest of his life. He had to spend winters abroad in such places as Egypt, Switzerland and Italy. A business career being ruled out, he made lecturing and teaching his profession. Apparently he excelled in this type of work making good use of ingenious models which he constructed and used with great skill. In 1901, he was appointed as a Grade A lecturer to the staff of the Oxford and Cambridge University Extension Delegacy and Syndicate. Later, he was a principal candidate for the Gresham Lecturership in 1909, however, Mr. S. A. Saunder, after heated competition with Hardcastle, was eventually appointed to the Lecturership after the electors had difficulty making their choice.

Hardcastle had earlier worked with Saunder on his lunar work regarding the number and accuracy of the measured positions on which the standard maps of the Moon were based. From his home in Crowthorne, Hardcastle had made over 20,000 mircometrical measures of lunar features, Saunder stated that the accuracy of this work was due to Hardcastle (see Memoirs of the Royal Astronomical Society Vol. 57, part 1, 1908, p.48). Hardcastle’s health had apparently improved for his appointment by Archbishop Crozier to succeed Dreyer was confirmed in 1916.

The British Calculator, Model C was manufactured sometime between 1904 and 1915.

FOR FURTHER INFORMATION PLEASE CONTACT: John McFarland at the Armagh Observatory, College Hill, Armagh, BT61 9DG. Tel.: 028-3752-2928; FAX: 028-3752-7174; jmfat signarm.ac.uk.

External Links:
Other images of this type of calciulator
Other British Calculator models
Report on the BBC website

Last Revised: 2013 June 21st