There is also the double ratio, or proportion as in x:y :: s:t
The equals sign "=" was promoted since "no two things can be more equal", or
"And to auoide the tediouſe repetition of theſe woordes : is equalle to : I will ſette as I doe often in woorke vſe, a paire of paralleles, or Gemowe lines of one lengthe, thus: =, bicauſe noe .2. thynges, can be moare equalle."