The common tools were all on the top layer of the box.

You just put on layers of clothing like the Chinese did.

They have no known effects at all on the ozone layer.

So these books may not stay on the top layer of the coffee table forever.

There is fresh snow on the top layer of trees.

Like most things in this nation, built on layers of the past, physical and mental, it is not always easy to explain.

She then added more hot rocks on top and a layer of dirt.

For those who created them, the foundations have taken on layers of significance.

That must have a profound effect on the ozone layer.

Pressure at any point on the upper layer forces the two layers into contact.