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As is typical, the installation firm we selected used a sophisticated device called a pyrometer to measure the solar radiance received on our roof.

In a muffle, in heated sand, with hot pieces of flat iron, and in boxes heated to the requisite temperature in an oven, the temperature being indicated by a pyrometer or heat-gauge.

When the "new" stove was on, and the "old" one lit for reheating, I went to the pyrometer shanty.

In the F�ry radiation pyrometer this difficulty is obviated, as the instrument may be placed at a considerable distance from the furnace.

With the pyrometer at three hundred and fifty, it is hardly prudent to pass to thirty.