002.389.Idrija

Idrija Mercury Heritage Management Center, Bazoviška 2, SI-5280 Idrija

Public

Republic of Slovenia

/

Daily life

The toggle switch consists of a round cast iron washer, which has a convex channel shaped like a letter S, with the two mercury pipes inserted in the two ends. The front side of the pipe is pointed, the back side is evenly fused. The back bottom part of the tube has two inserted and fused coper conductors (+/–), which are isolated in the plastic packs. The ends of the conductors are in the form of a washer and are attached with a nut to the parent bearings, which are fixed on the upper part of the cast iron washer. The conductive copper wires are attached to the same bearings, but were initially led from the switch. At the bottom, on the washer, there are two threaded screws, through which the washer is attached to the next item. The bottom side also has a small opening through which the series of electrical circuits is led. The washer is red.

Length 20 cm, width 16.5 cm, height 26.5 cm.

Glass, mercury, copper, cast iron, plastic.

1960s

Manufacturer information is not known.

The toggle switch was used at the export shafts of the Idrija Mercury Mine. In order to keep the carts with ore stable during the loading into the cage of an export shaft, the steel supporters or “sedalke” were pushed under the cage. When the carts were loaded, the supports were removed and the transport path was released. All the delivery areas had to have an appropriate signalling device, which allowed communication between the tensioners on the delivery areas and the engineers at the export machine. To avoid mistakes and thus accidents, the toggle switches were built on the supporters in the Joseph's shaft in 1955, which signalled to the export machine engineer whether the shaft profile was clear. The mercury moved if the cart incline was not correct and the circuit was interrupted, which was immediately reported to the engineer. From 1960, these switches were also installed at the Francis’ shaft.

The toggle switch is being preserved, secured and presented as important mining heritage of Idrija with exceptional universal values. It is a part of the CUDHg Smelting Collection. Visitors can view it within the permanent museum display “From Ore to Mercury Drops” in the Hg Smelting Plant, which represents the characteristics and the versatile use of mercury in science, technology, medicine, culture and every day life. Within the exhibition the object is placed in the segment of electrical conductivity and it represents the usefulness of mercury for technical devices and practical solutions.

Francis’s Shaft of the Idrija Mercury Mine.

Hg Smelting Plant (From Ore to Mercury Drops), Arkova 50, SI-5280 Idrija

The toggle switch is well preserved. Additional interventions are not necessary. Security of the premise is taken care off.

good

Regular seasonal maintenance.

- CUDHg Inventory Book.

Mestni muzej Idrija

Miha Kosmač

17. 3. 2018

Never