Mr. T.H. Easterfield scholar of Clare College, Cambridge, then read a paper on “Heat, what it is and what it does.”

Mr. Easterfield began his paper by pointing out that though all people knew the difference between hot and cold weather, no person’s senses could be relied upon to tell accurately how much hotter one day was than some other day, or one body than some other body.

He then showed by experiment that solids, liquids, and gasses all expand when heated and contracted when cooled. A red hot iron was fixed tightly in a cast-iron frame; upon cooling, the contraction of the bar broke the frame in which it was placed. He then briefly described how thermometers are made and graduated, and explained the differences between the thermometer scales in common use.

The lecturer then passed on to the subject of quantity of heat, and pointed out that two different bodies, though of the same size and temperature, might contain different quantities of heat. This he proved by placing bullets of lead and zinc at the same temperature upon a cake of wax. The zinc contained more heat than the lead and quickly dropped through the wax cake, but the lead did not posses heat enough to melt a hole through the wax.

Speaking of latent heat or the heat absorbed by a body upon changing its state, he showed that steam had a much greater heating effect than boiling water. He then explained that heat might be conveyed away from a body in three different ways, and that all bodies did not conduct heat at the same rate which was proved by experiments with bars of wood, iron, and copper.

Mr. Easterfield went on to say what heat was, and pointed out the errors in caloric theory, which was formerly so popular. He then alluded to experiments by Sir H. Davey, Joule, Hirn, and others which proved that mechanical work could be converted into heat, and the heat back again into the same amount of mechanical work.

Owing to the time taken up by the lecture and experiments a short discussion only followed.”