Verify out these cylindrical grinding photos:
Harbour Tours – Portsmouth Harbour – The Round Tower
Image by ell brown
On the Harbour Tour in Portsmouth Harbour.
Heading back towards Spinnaker Tower.
The Round Tower
Grade I listed creating.
SZ6299 BROAD STREET, The Point
774-1/11/457 (West side)
30/10/69 The Round Tower
(Formerly Listed as:
BROAD STREET, The Point
Square Tower Kings Stairs Sallyport
18 Gun Battery Round Tower Flanking
The Round Tower fortification, now museum. c1415. Ground floor
reconstructed c1538-40. 2 upper storeys added probably late
C17 by Sir Bernard de Gomme and remodified early C19, possibly
for adaptation as a Martello Tower. Top raised and
reconstructed and adapted as a gun platform c1850. Restored
late C20. Ashlar stone. Roof asphalt paved.
3 storeys separated by stone string bands, decrease storey
projects. Cylindrical. Entrance facing Board Street has a
two-leaf panel door each leaf with a 6-pane glazed upper panel,
set below a cambered stone arch. Facing the harbour on north
and west sides are three gun ports every set below a flat segmental
arch. 3 other gun ports were blocked up most likely late C17 by
Sir Bernard de Gomme.
INTERIOR: rebuilt early C19 was reconstructed and has a big
central stone column with brick vaulting, casements formed
behind the surviving gun ports.
(Balfour A: Portsmouth: London: 1970-: 15 Corney A:
Fortifications in Old Portsmouth: Portsmouth City Museums:
1965-: 30, 31 AND 32 Lloyd DW: Buildings of Portsmouth and
its Environs: Portsmouth: 1974-: 35,54-56,78,79,102 The
Buildings of England: Pevsner N & Lloyd D: Hampshire and the
Isle of Wight: Harmondsworth: 1967-: 422).
Listing NGR: SZ6292699463
This text is a legacy record and has not been updated because the creating was initially listed. Specifics of the building may possibly have changed in the intervening time. You must not rely on this listing as an correct description of the creating.
Source: English Heritage
Massive-scale Fractal Motion of Clouds
Image by NASA Goddard Photo and Video
NASA image acquired September 15, 1999
This Landsat 7 image of clouds off the Chilean coast close to the Juan Fernandez Islands (also known as the Robinson Crusoe Islands) on September 15, 1999, shows a special pattern referred to as a “von Karman vortex street.” This pattern has lengthy been studied in the laboratory, exactly where the vortices are produced by oil flowing past a cylindrical obstacle, making a string of vortices only numerous tens of centimeters extended. Study of this classic “flow past a circular cylinder” has been quite important in the understanding of laminar and turbulent fluid flow that controls a wide range of phenomena, from the lift beneath an aircraft wing to Earth’s weather.
Here, the cylinder is replaced by Alejandro Selkirk Island (named soon after the accurate “Robinson Crusoe,” who was stranded here for numerous months in the early 1700s). The island is about 1.five km in diameter, and rises 1.6 km into a layer of marine stratocumulus clouds. This kind of cloud is critical for its powerful cooling of the Earth’s surface, partially counteracting the Greenhouse warming. An extended, steady equatorward wind creates vortices with clockwise flow off the eastern edge and counterclockwise flow off the western edge of the island. The vortices grow as they advect hundreds of kilometers downwind, generating a street 10,000 occasions longer than these created in the laboratory. Observing the very same phenomenon extended more than such a wide variety of sizes dramatizes the “fractal” nature of atmospheric convection and clouds. Fractals are characteristic of fluid flow and other dynamic systems that exhibit “chaotic” motions.
Each clockwise and counter-clockwise vortices are generated by flow around the island. As the flow separates from the island’s leeward (away from the source of the wind) side, the vortices “swallow” some of the clear air over the island. (Significantly of the island air is cloudless due to a regional “land breeze” circulation set up by the larger heat capacity of the waters surrounding the island.) The “swallowed” gulps of clear island air get carried along inside the vortices, but these are quickly mixed into the surrounding clouds.
Landsat is unique in its potential to image both the little-scale eddies that mix clear and cloudy air, down to the 30 meter pixel size of Landsat, but also obtaining a wide sufficient field-of-view, 180 km, to reveal the connection of the turbulence to big-scale flows such as the subtropical oceanic gyres. Landsat 7, with its new onboard digital recorder, has extended this capability away from the handful of Landsat ground stations to remote places such as Alejandro Island, and as a result is steadily providing a international dynamic picture of evolving human-scale phenomena.
For much more specifics on von Karman vortices, refer to climate.gsfc.nasa.gov/~cahalan.
Image and caption courtesy Bob Cahalan, NASA GSFC
Instrument: Landsat 7 – ETM+
NASA Goddard Space Flight Center enables NASA’s mission by means of four scientific endeavors: Earth Science, Heliophysics, Solar Program Exploration, and Astrophysics. Goddard plays a leading role in NASA’s accomplishments by contributing compelling scientific expertise to advance the Agency’s mission.
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Bourke’s Luck Potholes, Blyde River, South Africa
Image by Pet_r
Bourke’s Luck Potholes, Blyde River Canyon location Mpumalanga, South Africa
"This all-natural water feature marks the beginning of the Blyde River Canyon.
Through numerous eons the swirling whirlpools which take place as the Treur
River plunges into the Blyde River, caused waterborne sand and rock to grind
massive, cylindrical potholes into the bedrock of the river.
The Potholes were named following a gold digger, Tom Bourke, who staked a claim
nearby. Although his claim did not create a single ounce of gold, he
appropriately predicted that huge gold deposits would be located in the region.
The Potholes is situated 35km north of Graskop town on the R532 road. The
informative visitors centre specifics some of the interesting organic and
socio-historic characteristics and is the starting point of the 700m walk to the