» Wollaston Wire (0275)
Immagini
DESCRIPTION
Exhibit 275 is a supply of Wollaston wire made of platinum (or an alloy of platinum and 10% rhodium) stretched to reach a diameter less than 0,013 mm and down to 0,00063 mm. The Wollaston method which permits obtaining such thin wires without breaking consists in inserting the wire in a coat of silver and lengthening them until the desired diameter is attained. The wire is delivered along with its silver covering which is removed with solvents that have no effects on the central wire; nitric acid, a solution of 10% of potassium cyanate or hot concentrated sulfuric acid.This wire was acquired as a repair for the wire electrometer (exhibit 254) and is wound on a wood spool marked HB (The trademark of 'Hartmann & Braun' and conserved in a metal box. The specified diameters are 0,001 mm (internal) and 0,05 mm (external)
ISCRIZIONI
- Sulla parte superiore della scatola compare la scritta seguente: "32129 Pos: Ga+Go"
- Sul rocchetto, insieme con il logo del costruttore, è scritto: Wollastondraht
BIBLIOGRAPHY
Dati Catalografici
| Data di costruzione: | --- |
|---|---|
| Data di carico: | Ignota |
| Nr. Inventario: | Ignoto (Ignoto) |
| Costruttore: | Hartmann & Braun |
| Materiale: | metallo |
| Dimensioni: | Lunghezza del filo: circa 13 cm |
| Conservazione: | ottimo |