Are You Giving Me a Line?
Running down the coast of California is a big one of these -- the San Andreas
fault line
On March 9, 1862 these 2 ironclads fought for 4 hours with neither ship receiving much damage
the Monitor & the Merrimac
The Latin word charta, "paper", helped give us this word for mapmaking
cartography
The U.S. Air Force maintains this 24-satellite system that many depend on
GPS
A scientific vessel, Boaty does its work for the NOC, Britain's National Centre of this -ography
oceanography
Until the early '70s, this Moscow-Washington link had no speech facilities -- it was a teletype
the Hot Line
In this 1805 battle Lord Nelson split Admiral Villeneuve's fleet in half & then proceeded to destroy each half
Trafalgar
It's the ratio that indicates the size of an area that a map represents, for example 1:2,500 miles
a scale
On a 3D topographic map, contour lines are used to identify points that have the same this
altitude (elevation)
Boaty isn't a submarine, or boat, for that matter, but this type of sub that's remotely operated and used to explore
a submersible
"Scabs" cross them
picket lines
DAILY DOUBLE : In a 1588 battle this fleet commanded by Medina Sidonia lost 63 ships due to high winds & the British navy
the Spanish Armada
Able to change naturally over time, an ambulatory boundary on a map is formed by one of these
a river (or any body of water)
The OED says a demonym is a name for residents of a place, like this standard name for people living in Manchester, England
Mancs (Mancunians)
Boaty is defined as this kind of ship, from the Greek for "self-ruled", & can travel far from its parent vessel
autonomous
It's 60 feet from the head pin on an alley
the foul line (in bowling)
The 1st extensively recorded naval battle was in 480 B.C. at Salamis where this Greek city-state beat the Persians
Athens
Latitude & longitude are examples of the number pairs that in the Cartesian system are called these
coordinates
You'll find each of these 2 geographic entities at 90 degrees latitude
the North and South Pole
(Kelly of the Clue Crew shows a map on the monitor.) Boaty measured Antarctic currents near the southern island group that shares its name with an archipelago off northern Scotland called this
the Orkney Islands
In 1957 this chain of about 60 radar sites along the 70th Parallel went into operation
Distant Early Warning (DEW) Line
The U.S. lost the destroyer Hammann & the aircraft carrier Yorktown in this June 1942 battle in the north Pacific
Midway
If you go online for directions to the offices of this website owned by AOL, type in 1555 Blake St., Denver
MapQuest
"Think over" this Scottish term for a cape, like the one "of Kintyre" peninsula
a mull
Holiday SURPRISE : Christmas island in this ocean received its name on Christmas Day 1643
Indian Ocean