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Section 5 Applying Technology: Producing Products and Structures
Academic Connections: Communication
Word Origins
Probably most people would be happy to have their names
become part of everyday language as a result of their inventions.
John McAdam, a Scottish engineer who experimented with road
construction, might be doubly pleased. His work with roads has
resulted in two words in common use today.
As described in this chapter, John McAdam
developed the crushed-stone road. This new type
of road had three layers of crushed rock compacted
into a solid mass. The road was also made slightly
convex. McAdam’s design improved roads tremen-
dously because now the traffic load was spread,
and rainwater ran off the surface. We are now more
familiar with this type of roadway through the use of
the term macadam.
The other word is even more familiar and is
also related to roads. In an effort to improve roads
even more, people used tar to bind the crushed
rock together. This process was given the name
tarmacadam or, as we now call it when we use it on
runways, tarmac. Modern roads are still built using
John McAdam’s principles. Can you find another
common word we use today that is based on some-
one’s name and invention?
Figure 17-17. A cross-sectional diagram of a finished wall. The photo shows brick being
applied as a siding material.
Ceiling joist
Ceiling
Brick
Sheathing
Stud
Flooring
Subfloor
Drywall
Floor joist
Fresh asphalt (tarmac).
©iStockphoto.com/PeskyMonkey
An asphalt road, a blacktop
road, or a tarmac road.
©iStockphoto.com/resonants