Charles's law 
(chärlzĭz)
(chärlzĭz)n.
The physical law stating that the volume of a fixed mass of gas held at a constant pressure varies directly with the absolute temperature.
[After Jacques Alexandre César Charles (1746-1823), French physicist and inventor.]
- keep nose clean
- keep nose to the grindstone
- keep off
- keep (one's) chin up
- keep one's chin up
- keep one's end up
- keep one's eyes open
- keep (one's) eyes open/peeled
- keep one's eyes peeled
- keep one's fingers crossed
- keep (one's) head
- keep one's head
- keep (one's) nose clean
- keep one's nose clean
- keep one's nose to the grindstone
- keep one's peace
- keep one's place
- keep (one's) powder dry
- keep one's powder dry
- keep (one's) shirt on
- keep one's shirt on
- keep one's weather eye open
- keep one's wits about
- keep one's wits about one
- keep pace