A speculum includes an upper bill, a lower bill downwardly of the upper bill, a yoke moveably joining the upper bill to the lower bill, and a ratchet to hold the upper bill and lower bill at a position relative to each other, the ratchet including teeth facing upwardly to selectively hold the upper bill and lower bill. When the ratchet is moved downwardly, the upper bill may pivot freely on the yoke. When the ratchet is moved upwardly, the upper bill is fixed against pivoting. In an example, the yoke includes a pivot about which the upper bill pivots when the ratchet allows and holds the upper bill in position against pressure on the upper bill. A latch prevents the yoke from being removed from the lower bill. Guides allow the upper bill move vertically on the lower bill through the yoke.
