Page:Reflections on the Motive Power of Heat.djvu/255

Rh The other bulb may be warmed either by boiling liquid or by fire.

Water, alcohol, steam, ether, mercury, acetic acid, sulphide of carbon.

The operation may be repeated and add the results.

To measure the temperature acquired by the air introduced into a vacuum or space containing previously rarefied air.

If the vacuum is made under the glass receiver of an air-pump, and the cock admitting the outer air be suddenly opened, the introduction of this air will cause a Bréguet thermometer to rise to 50° or 60°.

To examine the movement of this thermometer when the reintroduction takes place only by degrees, to compare it with the movement of the manometer.

Construction of a manometer which may give the pressure almost instantaneously.

Imagine a capillary tube bent into a spiral at one end, and having one extremity closed, the other open. This tube will be perfectly dry and a small index of mercury may be introduced into it. The diameter of the tube will be small