Fig. 37.
Fig. 37 shows the special form of insulator used. It is made of the highest grade glaze filled porcelain, and the screw is passed into it and holds against the lower end as far away from the wire as possible.
Glass tubes should be passed over the wires wherever they come near any metallic object, that is, within sparking distance.
Edwards’ Condenser System.
This system differs from the foregoing in that the spark-gaps are connected in multiple, instead of series, and each burner is provided with a small but efficient condenser.
Fig. 38.
It prevents trouble should a wire break between burners, in which event only one burner would be out of commission, whereas in the first method, the whole number in that series would suffer. It is also more sure in action and presents less liability of the spark jumping to the ground. The burner pillars need not be made of porcelain or lava; in fact, the electrodes can be readily attached to the existing burner. Fig. 38 is a condenser consisting of a small oval piece of mica, on each side of which is fastened, with insulating varnish, a spatula-shaped piece of tinfoil. One foil sheet is attached to the line, the other to the burner electrode. These condensers must not be allowed to get wet or their efficiency will be impaired.
