Page:Reflections on the Motive Power of Heat.djvu/241

Rh injurious to society? Have they not rather included in the same proscription religion and the abuse of it?"

"The belief in an all-powerful Being, who loves us and watches over us, gives to the mind great strength to endure misfortune."

"A religion suited to the soul and preached by men worthy of respect would exercise the most salutary influence upon society and customs."

Up to the present time the changes caused in the temperature of bodies by motion have been very little studied. This class of phenomena merits, however, the attention of observers. When bodies are in motion, especially when that motion disappears, or when it produces motive power, remarkable changes take place in the distribution of heat, and perhaps in its quantity.

We will collect a few facts which exhibit this phenomenon most clearly.

1. The Collision of Bodies.—We know that in the collision of bodies there is always expenditure of motive power. Perfectly elastic bodies only form an exception, and none such are found in nature.