There are two electric wires to the intake manifold mounted horn in the mid-1930’s. They are protected by a zinc plated conduit between the two horn contacts and where they connect to the main wiring harness beside the six cylinder Chevy engine.
The 1936 and earlier 207 engine manifold does not have a connection for the conduct from the horn. Therefore, it leaves the horn and runs beside the engine valve cover forward and down to the main wiring harness. A clip stabilizes the conduit by using a bolt on the water pump.
The first two years of the 216 engine [1937-38], this conduit also extends between the horn and wiring harness. It lays over the intake and then vertically down to the main wiring harness. A clip now secures the conduit to the new manifold horn extension bracket.
If it seems confusing, these photos should make it much easier to understand. In summary, the two different ways the horn mounts to the intake manifold results in the 7/16th conduit protecting the two wires from accidental damage over the years.