This device was made from a cleverly produced matrix of magnesium oxide which did not need to be supported by a platinum wire cage, and was exhibited in the Crystal Palace exhibition of 1883.
32.
Pure iridium is very difficult to pull into small diameter wires; at the same time, platinum has a low Young's modulus which makes pure platinum wires bend easily during the insertion in nervous tissue.
33.
The silver cladding is etched off a short piece of the composite wire, leaving an extremely fine platinum wire; this is supported, on two heavier silver wires, in a loop inside a glass bulb.
34.
The sample is put into direct contact with a platinum wire, or placed in a quartz sample tube, and rapidly heated to 600 1000 �C . Depending on the application even higher temperatures are used.
35.
The latter included sets of ingeniously designed bottles for taking samples of air; their sealed necks were broken open by an electromagnetic actuator and re-sealed by heating the neck with an electric current running through an exposed platinum wire.
36.
The design had two drawbacks & mdash; a rather large temperature coefficient of " 1.15 mV / �C, and corrosion problems caused by the platinum wires alloying with the zinc amalgam connections where they enter the glass envelope.
37.
The action of this detector is based upon the fact that only the tip of a platinum wire a few thousandths of an inch in diameter is immersed in an electrolyte solution, and a small current can flow better in the direction across the point that makes the point more negative.
38.
Above "'F "'several holes are cut in the rubber tube at the level of "'G "', and from this point a fine platinized platinum wire extends through the lumen of the tube and is held in place by fusion to a bump on the inside of a short piece of glass tube at the level of "'I " '.
39.
The heat emitted by isinglass, for example, is different from that emitted by lampblack, and the heat emitted by cloth, or paper, differs from both . " Looking at an electrically-heated platinum wire, it is obvious to the human eye that the heat's spectral profile depends on whether the wire is heated to dull red, bright orange, or white hot.
