Links & References

Information Sources:

Dr Paul Harrison: HARRISON P (1991) A Series of Papers on the Early History and Development of Industrial Time Recorders - Paper 1 - Gledhill-Brook Time Recorder Co. Ltd, England, 1912-1964

The National Archives, Companies House, Grace's Guide, Stanley Security Products, Llewellin's Machine Company Ltd, IBM, Wikipedia, Barrie Smith, Google Patents,

And a special thanks to John Fothergill for his help, advice, and endless knowledge regarding time recorders.

Useful Links:

IBM History:

IBM Hursley Park Museum:

The Bundy Museum:

Antique Time Clocks:

Gledhill-Brook info:

Electrical Clock Information: