sprag vs stanchion

sprag

verb
  • To prop or sustain with a sprag. 

  • To check the motion of, as a carriage on a steep slope, by putting a sprag between the spokes of the wheel. 

noun
  • A billet of wood; a piece of timber, a similar solid object or constructed unit used as a prop. 

  • A young salmon. 

stanchion

verb
  • To erect stanchions, or equip something with stanchions. 

  • To confine by means of stanchions, typically used for cattle. 

noun
  • A vertical pole, post, or support. 

  • A framework of such posts, used to secure or confine cattle. 

How often have the words sprag and stanchion occurred in a corpus of books? (source: Google Ngram Viewer )