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#101898

20-515: Middle Harbour Creek , a tributary of Middle Harbour , is a youthful tide -dominated, drowned-valley estuary north–west of Sydney Harbour , in Sydney , New South Wales , Australia . Formed by the confluence of Bare Creek and Frenchs Creek , north of Davidson , Middle Harbour Creek is in the Garigal National Park and flows from Mona Vale Road in the north down to Bungaroo , where

40-447: A n ) {\displaystyle A=(a_{1},a_{2},\dots ,a_{n})} and B = ( b 1 , b 2 , … , b n ) {\displaystyle B=(b_{1},b_{2},\dots ,b_{n})} is given by That is, the i coordinate of the midpoint ( i = 1, 2, ..., n ) is Given two points of interest, finding the midpoint of the line segment they determine can be accomplished by

60-408: A compass and straightedge construction . The midpoint of a line segment, embedded in a plane , can be located by first constructing a lens using circular arcs of equal (and large enough) radii centered at the two endpoints, then connecting the cusps of the lens (the two points where the arcs intersect). The point where the line connecting the cusps intersects the segment is then the midpoint of

80-433: A navigational context, if one were floating on a raft or other vessel in the main stream, this would be the side the tributary enters from as one floats past; alternately, if one were floating down the tributary, the main stream meets it on the opposite bank of the tributary. This information may be used to avoid turbulent water by moving towards the opposite bank before approaching the confluence. An early tributary

100-444: A larger stream ( main stem or "parent" ), river, or a lake . A tributary does not flow directly into a sea or ocean . Tributaries, and the main stem river into which they flow, drain the surrounding drainage basin of its surface water and groundwater , leading the water out into an ocean. The Irtysh is a chief tributary of the Ob river and is also the longest tributary river in

120-412: A left tributary which is called Right Fork Steer Creek. These naming conventions are reflective of the circumstances of a particular river's identification and charting: people living along the banks of a river, with a name known to them, may then float down the river in exploration, and each tributary joining it as they pass by appears as a new river, to be given its own name, perhaps one already known to

140-410: A third stream entering between two others is designated the middle fork; or the streams are distinguished by the relative height of one to the other, as one stream descending over a cataract into another becomes the upper fork, and the one it descends into, the lower ; or by relative volume: the smaller stream designated the little fork, the larger either retaining its name unmodified, or receives

160-507: Is a tributary that joins the main stem river closer to its source than its mouth, that is, before the river's midpoint ; a late tributary joins the main stem further downstream, closer to its mouth than to its source, that is, after the midpoint. In the United States, where tributaries sometimes have the same name as the river into which they feed, they are called forks . These are typically designated by compass direction. For example,

180-625: The American River in California receives flow from its North, Middle, and South forks. The Chicago River 's North Branch has the East, West, and Middle Fork; the South Branch has its South Fork, and used to have a West Fork as well (now filled in). Forks are sometimes designated as right or left. Here, the handedness is from the point of view of an observer facing upstream. For instance, Steer Creek has

200-460: The better-known being the Bungaroo Track , Cascades Track, and Bare Creek track. The bushland surrounding the creek is rich in bloodwoods ( Eucalyptus gummifera ), scribbly gums ( Eucalyptus haemastoma ), and the narrow-leaved stringy bark ( Eucalyptus oblonga ). Middle Harbour Creek was first explored by Governor Arthur Phillip on an expedition from Manly Cove on 15 April 1788. The intention of

220-408: The creek becomes Middle Harbour. Its catchment area is approximately 77 square kilometres (30 sq mi). Access along the majority of the creek is easy with tracks from (the western shore) St Ives , East Killara , East Lindfield , (eastern shore) Belrose , Davidson , Frenchs Forest and Forestville . Day walks are popular with access to the creek along several well maintained fire trails,

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240-415: The designation big . Tributaries are sometimes listed starting with those nearest to the source of the river and ending with those nearest to the mouth of the river . The Strahler stream order examines the arrangement of tributaries in a hierarchy of first, second, third and higher orders, with the first-order tributary being typically the least in size. For example, a second-order tributary would be

260-411: The expedition was to discover food. The expedition camped on 16 April at Bungaroo, where the tidal Middle Harbour finishes and the creek begins. It is possible to follow the entire length of Middle Harbour Creek, or to do a circular bushwalk that covers the majority of its length on both sides of the creek. Tributary A tributary , or an affluent , is a stream or river that flows into

280-403: The main stream. Distributaries are most often found in river deltas . Right tributary , or right-bank tributary , and left tributary , or left-bank tributary , describe the orientation of the tributary relative to the flow of the main stem river. These terms are defined from the perspective of looking downstream, that is, facing the direction the water current of the main stem is going. In

300-410: The midpoint M of a segment AB is the projective harmonic conjugate of the point at infinity , P , of the line AB . That is, the point M such that H[ A , B ; P , M ] . When coordinates can be introduced in an affine geometry, the two definitions of midpoint will coincide. The midpoint is not naturally defined in projective geometry since there is no distinguished point to play the role of

320-463: The people who live upon its banks. Conversely, explorers approaching a new land from the sea encounter its rivers at their mouths, where they name them on their charts, then, following a river upstream, encounter each tributary as a forking of the stream to the right and to the left, which then appear on their charts as such; or the streams are seen to diverge by the cardinal direction (north, south, east, or west) in which they proceed upstream, sometimes

340-404: The point at infinity (any point in a projective range may be projectively mapped to any other point in (the same or some other) projective range). However, fixing a point at infinity defines an affine structure on the projective line in question and the above definition can be applied. The definition of the midpoint of a segment may be extended to curve segments , such as geodesic arcs on

360-409: The result of two or more first-order tributaries combining to form the second-order tributary. Another method is to list tributaries from mouth to source, in the form of a tree structure , stored as a tree data structure . Midpoint The midpoint of a segment in n -dimensional space whose endpoints are A = ( a 1 , a 2 , … ,

380-508: The segment. It is more challenging to locate the midpoint using only a compass, but it is still possible according to the Mohr-Mascheroni theorem . The abovementioned formulas for the midpoint of a segment implicitly use the lengths of segments. However, in the generalization to affine geometry , where segment lengths are not defined, the midpoint can still be defined since it is an affine invariant . The synthetic affine definition of

400-433: The world with a length of 4,248 km (2,640 mi). The Madeira River is the largest tributary river by volume in the world with an average discharge of 31,200 m /s (1.1 million cu ft/s). A confluence , where two or more bodies of water meet, usually refers to the joining of tributaries. The opposite to a tributary is a distributary , a river or stream that branches off from and flows away from

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