1905 - 60kV in Fog
Construction started on the cement plant that would be crucial
in rebuilding San Francisco after its 1906 earthquake. The location was
Davenport, just up the coast from Santa Cruz, CA.
Local electric power was
scarce and unreliable, so California Gas and Electric Corp. was engaged to build
a line to Davenport from Cupertino, west of San Jose. The route crossed the
Santa Cruz Mountains - an area famous for its heavy fog. Frank Baum, consulting
engineer for Cal. G.& E., had been in charge of the Colgate line and was well
aware of how difficult it was to insulate against heavy fog.
He designed and patented a new style insulator specifically for this
situation. No sign of this insulator had been found until 2002, when
Paul Greaves and Mike Spadafora recovered the first specimen near
Saratoga Gap. Elton designated this new type M-4604. The top is exactly
like the one shown in the patent, but the skirts do not have rings.
Modern petticoated tops trace their lineage to this insulator. The Baum
story can be found on Elton’s
www.r-infinity.com web site. In 2003, Carver
and Barb were hunting near the middle of the line and found one
spectacular unit (shown at right) and one kitsulator. The beautiful
bell-shaped third skirt has a “Cal. G. & E. Corp” inspector’s stamp on
its top, as shown below.