One point of the compass is placed at the center of the protractor and an elastic band is looped between the points.
He was using a protractor, which was divided into Galactic degrees.
It is also fairly accurate to run a line at any angle to a given line by sighting along two pins stuck in a protractor.
protractor: that which extends or lengthens out: applied to muscles.
The protractor has a graduated disk, and is adjustable so it can be disposed at any angle.
At that point find, by means of a protractor, the angle a projection of the chord makes with the face of the beam.
A line is then drawn from A to the point marked and the angle F is measured with a protractor.
Then, if we have a protractor, we may apply it to the lines and see how many degrees of angle they contain.
Off and on I try and keep up my Euclid and do a rider over my lunch, and I just keep a protractor handy.
The student should have and use a protractor, such as is furnished with this book, for the numerous exercises which are to follow.
1610s, "one who lengthens (an action)," from Medieval Latin protractor, agent noun from Latin protrahere "to draw forward" (see protraction); sense of "instrument for drawing angles" first recorded 1650s.
protractor pro·trac·tor (prō-trāk'tər, prə-)
n.
A muscle that extends a limb or other part.