Alamo Plaza Bollards
It'sInMyYardHenge - Day 8
South Bank
out of nowhere
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East Buxton Lime Works
Building the power station
Paul McCartney's Case
A Case History 1
A Case History 2
Fred G. Redmon Bridge, Washington state, USA
erica's_purple_basement
Fred G. Redmon Bridge
Fred G. Redmon Bridge
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Pre-architecture
Concrete for water
Sea defence
stadtaffe
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foundations
reinforced
crane
Die Crew
1300
Lines
übergang
Broad Street Bridge
Broad Street Bridge
201008225025
Fountain on the deck
Gully view
Trellick Tower
Rio Chirri
nice point of view
Sleepers
New Track at Nadrazi Cercany, Cercany, Bohemia (CZ…
Alexandra Road Estate 2
See Spot Dig
Mushrooms & Gnomes
Alexandra Road Estate 1
Oh, yes I was !
The Best Job in Berlin
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Buns up!
New Change
City
nothing exceptional - 3
Signage I
Signage II
Signage III
Head loads
dsc_6737
Just visiting....
Awaiting
Building
Concrete towers
Recharging in progress...
Lady racer...
A Tank in Concrete
Firearms in Concrete
Swiss roll
till we meet
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Early warning
During the first world war there were a number of air attacks made upon the North-East coast by German aircraft. Zeppelins raided the area fifteen times between April 1915 and November 1917.
Defence against these raids was very limited and depended on knowing when aircraft were approaching and from what direction. To this end a series of listening stations were erected along the coast (and also in the south of England) in the form of 'sound mirrors'. This example, now sitting in the midst of a Redcar housing estate, and listed Grade II, was constructed by the Royal Engineers in 1916. It is about 17ft high.
The sound of the approaching aircraft was reflected off the concave surface and into a receiving trumpet mounted on a steel column in front. This was connected to the listening operator by a stethoscope and this was moved to find the part of the dish producing the most sound, which indicated the direction of approach. At least the local populace could then be given advanced warning of the impending raid.
Acoustic listening devices of various shapes were constructed along the coasts until the 1930s after which they began to be replaced by Radar.
Defence against these raids was very limited and depended on knowing when aircraft were approaching and from what direction. To this end a series of listening stations were erected along the coast (and also in the south of England) in the form of 'sound mirrors'. This example, now sitting in the midst of a Redcar housing estate, and listed Grade II, was constructed by the Royal Engineers in 1916. It is about 17ft high.
The sound of the approaching aircraft was reflected off the concave surface and into a receiving trumpet mounted on a steel column in front. This was connected to the listening operator by a stethoscope and this was moved to find the part of the dish producing the most sound, which indicated the direction of approach. At least the local populace could then be given advanced warning of the impending raid.
Acoustic listening devices of various shapes were constructed along the coasts until the 1930s after which they began to be replaced by Radar.
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