This page has been validated.
![](http://upload.wikimedia.org/wikipedia/commons/thumb/8/87/Operating_the_Comptometer_-_iii_-_Oil.png/500px-Operating_the_Comptometer_-_iii_-_Oil.png)
Oil.
If used only once or twice a week, oil about once in six months. If used eight hours a day right along by a rapid operator, oil about once in two weeks.
Put only a couple of drops each side of each numeral wheel through top corner of square holes in the register plate. Use any good typewriter or sewing machine oil.