The California Electrical Works was established due to the purchase of the Electrical Construction and Maintenance Company in 1878. 

The company dealt largely in wire products, telegraph poles, and insulators; however, constructing and maintaining telegraph and telephone lines also took place. 

In heavily forested areas, repair maintenance was frequent. Falling limbs would cause both the wire and insulator to break. To eliminate this time-consuming repair and to provide better service, a new device was needed to secure the insulator. 

A brass suspending mount holding the wire from the insulator was used. Both EC&M's and CEW's were used in this manner. This kept the insulator and wire intact should something strike the main line. 

Yosemite Valley is the best known area for this type bracket, "THE YOKE", and insulator. A single conductor line using the ground as a return was used to serve as a communication link between mines in the Sierras and Sonora. The line was made up of ramshorns from Sonora to a relay point in Yosemite Valley. This relay point is where the CEW's came into use. These insulators and brackets stretched a total of 23 miles to Bennetville Mine via Tuolumne. At this point the line continued through Bundy Mine and ended at Bodie mining town. The EC&M with a similar bracket was used. The insulators along these lines were all mounted on large trees in elevations as high as 10,000 feet above sea level. 

The CEW pictured was found between Yosemite Valley and Tuolumne. It dates back to 1881.