When the engineers drilled the water conduits, they bored an extra tunnel under the glacier to house our observatory.

Geologists and engineers drill core samples and conduct surface surveys searching for specific compounds and ores.

To test this technique, engineers first drilled boreholes 2 kilometres deep and 300 metres apart to form an underground reservoir of water heated by the hot dry rocks.

The army temporarily halted the search, which began Saturday after engineers drilled into the newly discovered tunnel in the demilitarized zone.

After the engineers drilled temporary holes in the mountain, for example, the geologists wanted to sample the gases coming from them.

Many of the cracks were discovered two years ago, and at that time engineers drilled holes in the paths of the cracks to stop them from expanding.

The engineers drilled all around the hole, during the afternoon, looking for thicker rock from which they could bridge the gulf.

The engineers drilled 4 posts into the wall to stabilize the structures, causing widespread uproar among both Jews and Muslims.

In communist days, exploration techniques were often wasteful as engineers simply drilled as many wells as possible to satisfy Moscow's quota demands, regardless of the productivity of each one.

To stop these flaws from growing, engineers drill holes in the end of the cracks and bolt steel reinforcement over the damaged area.