Grace's Guide is the leading source of historical information on industry and manufacturing in Britain. This web publication contains 162,259 pages of information and 244,500 images on early companies, their products and the people who designed and built them.
Grace's Guide is the leading source of historical information on industry and manufacturing in Britain. This web publication contains 147,919 pages of information and 233,587 images on early companies, their products and the people who designed and built them.
of Leatherhead.
1974 Manufactured five photoconductive cells with a peak spectral response at 7,000 angstroms, being more sensitive at the infra-red part of the spectrum.
1974 Developed a new fire alarm control system that consisted of a control unit and a separate power pack to provide two separate alarm conditions - fault warning and fire warning.[1]
Grace's Guide web site design is Copyright © 2021 by Grace's Guide Ltd. The text of this web site is available under the Creative Commons Attribution-ShareAlike License; additional terms may apply. By using this site, you agree to the Terms of Use and Privacy Policy. Maintained by Sapere Software