An example of analogy in popular science writing:
"Although in the solid state of matter the molecules are strongly bound to their places [sic], it does not mean at all that they are not affected by thermal agitation. Indeed, according to the fundamental law of heat motion, the amount of energy in every molecule is the same for all substances, solid, liquid, or gaseous at a given temperature, and the difference lies only in the fact that whereas in some cases this energy suffices to tear off the molecules for their fixed positions and let them travel around, in other cases they can only quiver on the same spot as angry dogs restricted by short chains."
George Gamow (1961) One, Two, Three…Infinity. Facts and speculations of science, Revised Edition, Dover Publications, Inc., New York.
I was unsure whether to consider this a fully-blown analogy or just an extended metaphor. There is a mapping between target and analogue (angry dogs – molecules in solid; quivering – thermal agitation; short chains – strong bonding), but it is not made very explicit for a non-specialist reader.
Read examples of scientific analogies
