The small stone drilling firm where Mr. Richter works offers no health coverage, and the family could not afford the more than $600 a month it would have cost to buy it on their own.
On his expeditions he collected ancient arrowheads, thin stone blades, drills made of bone, ceremonial stone axes, grinding stones and pottery shards.
There are many other special tools, including stone gouges, drills, toothed hammers (known as bushhammers or bouchardes), and, often used today, power-driven pneumatic tools, for pounding away the surface of the stone.
"On the Origins of the Dentist (With a Stone-Age Drill)" (news article, April 7) reports that in Neolithic Pakistan, dental services were "available to all," and not restricted to the elites of the village.
The Archaic toolkits included flaked stone knives, drills, and stemmed dart points.
Pipes were typically made of drilled stone or of hollowed wooden logs, although clay and lead pipes were also used.
A stone, un sasso, drilled with a hole, it was worn around the neck as a kind of proto-ID.
A land exercise, "Saber Strike", will follow, then "Jackal Stone", a special-forces drill.
Abrasive drilling in stone was well suited to the high-speed bow drill.
When a number of points have been fixed by drilling, the stone is cut away to the required depth.
