Full Idea
Boyle's Law generalises a mass of messy data culled from an apparatus; Snell's Law is an experimentally derived law deducible from theory; Newton's First Law derives from concepts and thought experiments; Mendel's Law used an experimental procedure.
Clarification
Snell's Law concerns the refraction of light
Gist of Idea
Laws can come from data, from theory, from imagination and concepts, or from procedures
Source
Rom Harré (Laws of Nature [1993], 1)
Book Reference
Harré,Rom: 'Laws of Nature' [Duckworth 1993], p.10
A Reaction
Nice examples, especially since Boyle's and Newton's laws are divided by a huge gulf, and arrived at about the same time. On p.35 Harré says these come down to two: abstraction from experiment, and derivation from deep assumptions.