Paul D'onofrio., Age 11, Of Somerville, Mass., for his question:

Where does lanolin come from?

If you have touched the fleecy coat of a sheep, you know that it feels heavy with tacky grease. Most of this fatty oil is removed before the silken threads are woven into woolen yarns and textiles. It is wool wax, and when cleaned and purified this wool wax is sold as lanolin. Pure lanolin is a thick, yellowish wax and quite sticky.

When mixed with water, the tacky wax breaks up into small droplets, forming an oily emulsion. In this state it becomes a useful base for ointments and face creams. Lanolin also is used to make shoe polishes and oily coats to protect outdoor metals from the weather.