Bailliart ophthalmodynamometer

Invented in 1917 by Bailliart and Magitot, the Bailliart ophthlamodynamometer was used for checking the arterial pulse pressure of the eye. One looked inside the eye with the ophthalmoscope and pressed against the outside of the eye with the plunger. When the retinal arteries started to pulsate, the diastolic (resting) pressure had been reached. When the pulsation stoppped, systolic pressure has been reached.