"It's a big black sphere, like a huge bowling ball."

It looks as though the big sphere is only transparent from the outside.

Then he slung the bag over his shoulder and moved to the big sphere that dominated the room.

This time it was big black spheres rolling across the countryside.

The Earth was a big, bright, blue sphere now, growing by the minute.

Well, let us choose it in the form of a big sphere.

When they had all changed clothes, Hunter opened the big sphere and helped them inside.

With his free hand, he spun the big sphere and watched it revolve.

He pushed a button on the control panel that opened the big sphere.

The bigger sphere has a lower density and is going to be more buoyant.