Construction, Maintenance, and Repairing of Aircraft Instruments JA Gordon Beaufort and Automatic/Manual switch requires the

and Automatic/Manual switch requires the proper electrical connection to toggle

describing its use

It has some slight water damage on one page

In addition to its reliability

Construction, Maintenance, and Repairing of Aircraft Instruments JA Gordon Beaufort and Automatic/Manual switch requires theThis 30 page document is a reprint by Henry Paulson & Co. of content of Construction, Maintenance, and Repairing of Aircraft Instruments by J. A. Gordon from London's Horological Journal. The Henry Paulson firm appears to have been engaged in the manufacturing and or marketing of precision instrument tools and equipment. It appears that they also published technical references and catalogs such as this in an effort to expand their service offerings to