This section is from the book "The Boy Mechanic Vol. 2 1000 Things for Boys to Do", by Popular Mechanics Co.. Also available from Amazon: The Boy Mechanic, Vol2: 1000 Things for Boys to Do.
Persons rowing boats, particularly beginners, find that the oars will slip out of the oarlocks, turn or fall into the water. This may be avoided by turning a screweye of sufficient size to prevent binding on the lock into the oar and placing it over the lock as shown at A, so that the pull will be against the metal. The oars will never slip or jump out, will always be in the right position, and it is not necessary to pull them into the boat to prevent loss when not rowing. The locks will not wear the oars, as the pull is on the metal eye. Place the eye so it will have a horizontal position on the side of the oar when the blade is in its right position.
Ill: The Screweye in Position on the Oar and over One Prong of the Oarlock