indicates how pressure and temperature can be related to the motion of atoms and moecules on a
statistical basis. Physics emerged as a separate science only in thc early 19th century; until that time a was oñen also a mathematician, philosopher, chemist, biologist, engineer, or even primarily a political leader or artist. Today the has grown to such an extent that with few exceptions modern have to limit their attention to one or two branches of the science. Once the fundamental aspects of a “CW field are discovered and understood, they become the domain of engineers and other applied scientists. The 19th-century discoveries inclcctricity and magnetism, for example, are now the province 0f Ciccińcal
and communicationengincers; the properties of matter discovered at me beginning of the 20m century