Wollaston process wire

In 1994, Dinwiddie and PyUdd [34,35] described the first combined SThM/AFM probes that employed resistance thermometry to measure thermal properties. These were fashioned from Wollaston process wire. This consists of a thin platinum/5% rhodium core (about 5 pm in diameter) surrounded by a thick (about 35 pm) silver sheath. The total diameter of the wire is thus about 75 pm. A length of wire is formed into a V and the silver is etched away at the apex to reveal a small loop of Pt/Rh which acts as a miniature resistance thermometer (Figure 2(a)). A bead of epoxy resin is added near the tip to act... 

Figure 73. A Wollaston resistive thermal probe (not to scale), including a section through Wollaston process wire.

Medium Energy EBW Detonator w/Wolla-ston Wire Bridge, shown in Fig 72. Wollaston wire is a coaxial bimetallic material made by inserting a wire of one material (usually gold or platinum) in a tube of another (.usually silver) after which the combination of tube and core is drawn thru dies to a smaller size. The outer tube may be dissolved by an acid leaving the core, which may be much smaller than a wire could be drawn by any other process. High temperature double-bore thermo-... 

Thomas Cock manufactured platinum by Wollaston s process, and Wollaston was associated with him for some time. In 1805, platinum crucibles could be bought for 17s. 6d. per oz., and wire... 

The similar chemical effects of frictional and voltaic electricity led him to conclude that they were identical, long before such a view became commonplace. Later, after perfecting the process of drawing extremely fine platinum wires, Wollaston constructed his "thimble battery", which was a very small galvanic cell capable of bringing a platinum filament to incandescence upon iimiersion in dilute vitriolic acid. Both demonstrations illustrate Wollaston s talent for eadiibiting natural phenomena by means of inexpensive "shirt-pocket" devices. 

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