Tangent lines to circles and Siuna: Difference between pages

Coordinates: 13°44′N 84°46′W / 13.733°N 84.767°W / 13.733; -84.767
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{{for|Seafarers International Union of North America (SIUNA)|Seafarers International Union of North America}}
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'''Siuna''' is a [[municipality]] in the [[Región Autónoma del Atlántico Norte]] [[Departments of Nicaragua|department]] of [[Nicaragua]].
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The town of Siuna was the site of a gold mine operated by several U.S. and Canadian corporations in the past. Along with Rosita and Bonanza Siuna forms the Mining Triangle of Siuna.
<!-- PROPOSED NAME CHANGE: Tangent lines to circles -->


Ground water in the area is contaminated with arsenic and mercury from the mining.<ref> Environmental Exposure and Fingernail Analysis of Arsenic and Mercury in Children and Adults in a Nicaraguan Mining Community[http://heldref-publications.metapress.com/index/751317285204L420.pdf]</ref>
In [[Euclidean geometry|Euclidean plane geometry]], '''tangent lines to circles''' form the subject of several theorems, and play an important role in many geometrical constructions and proofs. Since the tangent line to a circle at a point '''P''' is perpendicular to the radius to that point, theorems involving tangent lines often involve radial lines and orthogonal circles.


The town of the Siuna has a campus of [http://www.uraccan.edu.ni/ URACCAN (Universidad de las Regiones Autónomas de la Costa Caribe Nicaragüense)].
==Tangent lines to one circle==


'''With regards to the history of Siuna going back to the 1950s:''' My family, which included my parents, Allen and Marjorie Drebert along with my brother Doug and myself, Jim, moved from Toronto, Canada, to Siuna in 1957 where we spent 5 years until 1961. My father worked in a capacity of managing transportation and maintenance for La Luz Mining Company. We lived on the staff zone for all of the foreign workers on the top of a hill overlooking Siuna and the mine. My brother and I attended the one room school for all of the English speaking children which taught grades one to nine. After grade nine, the children or young adults had to be sent off to boarding school which would usually be back in their home country. My brother Doug and I, have very fond memories of our time growing up in Nicaragua. The mountain climate was ideal averaging between 75 and 85 degrees F. throughout the year. Check out some of the photos taken during our stay there. By: Jim Drebert. Anyone wishing to contact me regarding this article, please feel free to e-mail myself at: jimdrebert@hotmail.com
A tangent line ''t'' to a circle ''C'' intersects the circle at a single point '''T'''. For comparison, secant lines intersect a circle at two points, whereas another line may not intersect a circle at all. This property of tangent lines is preserved under many geometrical transformations, such as [[scaling (geometry)|scalings]], [[rotation]], [[translation (geometry)|translations]], [[Inversive geometry#Circle inversion|inversions]], and [[map projections]]. In technical language, these transformations do not change the [[incidence structure]] of the tangent line and circle, even though the line and circle may be deformed.


[[Image:Allen Drebert.jpg|thumb|My father, Allen Drebert at Rosita copper mine, who shot all of the following photos]]
The radius of a circle is perpendicular to the tangent line through its endpoint on the circle's circumference. Conversely, the perpendicular to a radius through the same endpoint is a tangent line. The resulting geometrical figure of circle and tangent line has a [[reflection symmetry]] about the axis of the radius.
[[Image:La Luz Gold Mine.jpg|thumb|Looking down on La Luz Gold Mine complex from staff zone pool]]
[[Image:Shaft Elevator.jpg|thumb|Another view of La Luz Gold Mine picturing the main shaft tunnel cable lift]]
[[Image:Processing Ore.jpg|thumb|Processing the gold ore at La Luz gold mine in Siuna]]
[[Image:Processing gold.jpg|thumb|Processing gold at La Luz Gold Mine]]
[[Image:Pouring gold.jpg|thumb|Pouring molten gold into ingot mold at La Luz Mine]]
[[Image:Gold Weight.jpg|thumb|Removing slag from gold ingot]]
[[Image:Weighing Gold.jpg|thumb|Weighing gold ingots]]
[[Image:Gold Mom.jpg|thumb|Mom checking out gold bar ingots]]
[[Image:Vehicle Maintenance Shop.jpg|thumb|Photo of La Luz Mines maintenance shop. My Dad, Allen Drebert, was responsible for the operation of this]]
[[Image:Mechanics.jpg|thumb|Photo of mechanics in vehicle maintenance shop. Does anyone from Siuna recognize yourself?]]
[[Image:Mechanics2.jpg|thumb|Another photo inside vehicle maintenance shop checking out a crankshaft]]
[[Image:Pay Day.jpg|thumb|Pay day at Siuna Gold Mine - just outside the main gate]]
[[Image:Siuna Street.jpg|thumb|Street scene in Siuna]]
[[Image:Siunapowerplant.jpg|thumb|Current powerplant in Siuna on property of former La Luz mine. As the sign shows the property is currently owned by Yamana (Toronto Canada).]]
[[Image:Open Pit.jpg|thumb|La Luz Mine original Open Pit where gold was initially surface mined. This ridge started to cave in with a large landslide during our time there. This is now a lake or lagoon as pictured below.]]
[[Image:siunalaguna1.jpg|thumb|Lagoon in the center of Siuna from La Luz mine today.]]
[[Image:Laguna Siuna.jpg|thumb|View of Lagoon in Siuna which was the initial Open Pit Mine. Photo compliments of Maria from Siuna.]]
[[Image:Maria at Laguna.jpg|thumb|Maria with Lagoon in background]]
[[Image:Siuna International Housing Campus.jpg|thumb|La Luz Mines International staff zone in Siuna.]]
[[Image:Staff Zone 2.jpg|thumb|Staff zone view of pool area and clubhouse at top of hill along with tennis court]]
[[Image:Brothers in Siuna.jpg|thumb|Brothers, Jim & Doug, at our pool on La Luz Mines staff zone]]
[[Image:Mom and Brothers.jpg|thumb|Mother with brothers at pool]]
[[Image:Dad and Mom in pool.jpg|thumb|Dad and Mom enjoying a swim]]
[[Image:Jim & Doug in Pool.jpg|thumb|Brothers enjoying a swim]]
[[Image:Jim in Pool.jpg|thumb|Jim enjoying a boat ride in pool]]
[[Image:Pool Mom.jpg|thumb|Mom at pool next to staff zone clubhouse and single men's living quarters]]
[[Image:laluzmineswimmingpole1.jpg|thumb|Same pool, now abandoned photo taken in September 2008.]]
[[Image:Tennis Court.jpg|thumb|Mom at the tennis court located next to playground]]
[[Image:Front Yard.jpg|thumb|View of Mom in our front yard with golf course in the background]]
[[Image:Snake on road.jpg|thumb|Friends Terry and John, our Mother, Doug and myself, Jim, on the right checking out snake that had been run down]]
[[Image:Snake Roadkill.jpg|thumb|Another photo of snake roadkill]]
[[Image:Country.jpg|thumb|A drive into the Nicaraguan wilderness - notice that there is nothing around except jungle and mountains]]
[[Image:Country Road.jpg|thumb|Another drive along one of the country roads]]
[[Image:Mule Train.jpg|thumb|A mule train - a popular mode of transport during these years]]
[[Image:Oxen.jpg|thumb|View of an Ox team]]
[[Image:Tannery.jpg|thumb|View of a tannery where they cure cow and horse hides]]
[[Image:Wash Woman.jpg|thumb|Woman washing cloths in a stream - no need for the Maytag Repair Man]]
[[Image:Classmates.jpg|thumb|Classmates in our one-room English school on staff zone]]
[[Image:Ball team.jpg|thumb|Our baseball team preparing for a game]]
[[Image:Ball Team.jpg|thumb|My baseball team at ball park next to Siuna airport runway]]
[[Image:Ball Team 2.jpg|thumb|La Luz baseball team at ball park next to airstrip]]
[[Image:Managua Market.jpg|thumb|Shopping at a Managua market]]
[[Image:Managua Market 2.jpg|thumb|Another view of Managua market street]]
[[Image:Craterlake 2.jpg|thumb|View of a volcanic crater lake in the Managua area with Lake Managua in the background]]
[[Image:Lake Managua 2.jpg|thumb|View of Lake Managua]]
[[Image:Lake Managua.jpg|thumb|View of Lake Managua from a vacation home we stayed in for a month]]
[[Image:Vacation House.jpg|thumb|Vacation house we stayed at just outside of Managua - note that we experienced a mild earthquake during our time there - the house was violently shaking for about 30 seconds which seemed like an eternity!]]
[[Image:Vacation House2.jpg|thumb|Another photo of Managua vacation house taken from the back yard]]
[[Image:1957 Chevy.jpg|thumb|Dad at Managua vacation house which included the use of a 1957 Chevrolet]]
[[Image:Prinzipolka Dock.jpg|thumb|Prinzipolka dock viewed from about half of the way out - note that bulk carrier is off-loading sulfur which is used for the smelting process of gold, copper and other metalic ores - it was then loaded onto semi-trailers and transported up river on a large barge to Alamacamba and finally via mountain roads to Siuna and Rosita and Bonanza mines]]
[[Image:Sulfur on Dock.jpg|thumb|View of sulfur that has been off loaded from cargo ship and being stored along main pier]]
[[Image:River Mouth.jpg|thumb|Nearing the mouth of the Prinzapolka River on the Caribbean Mosquito coast]]
[[Image:Cargo Ship.jpg|thumb|Off loading supplies from cargo ship for the mines - note that I ended up becoming a Marine Engineer when I finally grew up - maybe our tour of the cargo ship inspired me]]
[[Image:Cargo Ship 2.jpg|thumb|Doug and I at the helm of the cargo ship]]
[[Image:Sulfur Barge 2.jpg|thumb|Barge being motored up river on the Prinzapolka carrying trailer fulls of sulfur for Siuna and Rosita and Bonanza mines, used in smelting the ores.]]
[[Image:Sulfur Barge.jpg|thumb|Semi-trailers loaded with sulfur for smelting being off loaded in Alamikamba on the Prinzipolka River for transporting the the mines - also note yacht belonging to Mr. McGowan, president of La Luz Mines]]
[[Image:Dry Season.jpg|thumb|View of Alamikamba on the Prinzapolka during the dry season - where barges of sulfur and sundry mining supplies are off loaded and trucked overland to Siuna and Rosita and Bonanza mines - note the low river level during the dry season which occurs during the winter months]]
[[Image:Rock Crusher.jpg|thumb|Rock crusher near Alamikamba used to build and maintain all of the gravel roads]]
[[Image:Storage Tank.jpg|thumb|Setting up a storage tank at Alamikamba]]
[[Image:Storage Tank 2.jpg|thumb|Another view of storage tank]]
[[Image:Father and son.jpg|thumb|Father and son at Prinzapolka dock on Caribbean coast owned by La Luz Mining Company]]
[[Image:Beach Cabins.jpg|thumb|Cabins on Caribbean Mosquito coast at Prinzapolka owned by La Luz Mines for the accommodation of their employees on vacation or on buisness]]
[[Image:Beach Boys.jpg|thumb|Doug and I getting in some extended play-time on beach at Prinzapolka near sundown]]
[[Image:Beach 3.jpg|thumb|Dad teaching me the finer points of seamanship in the Caribbean]]
[[Image:Beach 4.jpg|thumb|Mom and Doug enjoying the sand and surf]]
[[Image:Beach 5.jpg|thumb|Another view of the beautiful mosquito coast - notice the lack of tourists]]
[[Image:Prinzipolka River.jpg|thumb|Doug and I going down Prinzapolka River towards Caribbean via tug and barge shooting a 22]]
[[Image:Mosquito Indians.jpg|thumb|Mosquito Indian family abode along the Prinzapolka River - note their mode of transport - one dugout, aka hollowed out log]]
[[Image:House 2.jpg|thumb|House under construction along the Prinzapolka River - no need for a building permit]]
[[Image:Mosquito Family.jpg|thumb|Mosquito family living in Prinzapolka]]
[[Image:River Nests.jpg|thumb|Mocking bird nests in large tree along Prinzapolka River]]
[[Image:Large Tree.jpg|thumb|Mom by a large tree close to #1 golfcourse green]]
[[Image:Golf Course 3.jpg|thumb|View of Mom on golf course hole #3 - notice the vintage pickup trucks which were all numbered on their doors]]
[[Image:Golf Course 1.jpg|thumb|View of golf course hole #4 & #5 from the front porch of our residence]]
[[Image:Golf Course.jpg|thumb|View of golf course green and fairway #5 - note that airstrip is located in valley beyond golf course]]
[[Image:Gold course hole number 4.jpg|thumb|Mom teeing off on hole number 4 on our 5 hole golf course surrounding Staff Zone]]
[[Image:Dad chipping.jpg|thumb|Dad chipping to #5 green]]
[[Image:Jim putting.jpg|thumb|Jim and Doug putting on #1 green]]
[[Image:Jim on Hole -1.jpg|thumb|Jim golfing on hole #1]]
[[Image:School Day.jpg|thumb|Brothers on way to school]]
[[Image:Playground Ball.jpg|thumb|Brothers practicing baseball on staff zone playground next to school]]
[[Image:Ei River.jpg|thumb|Ei river upstream of the hydro electric dam]]
[[Image:Ei River Dam.jpg|thumb|Ei River Dam which supplied all of the hydro electric power for the mines and the region]]
[[Image:Hydro 4.jpg|thumb|Photo taken behind the dam - note the overflow during the rainy season]]
[[Image:Spillway Pipe.jpg|thumb|Ei River Dam spillway pipe supplying water to turbines]]
[[Image:Hydro 2.jpg|thumb|Photo of Ei River Hydro Electric Plant area]]
[[Image:Hydro 3.jpg|thumb|Photo of Ei River Hydro Electric Power Plant area]]
[[Image:Ei Generators.jpg|thumb|Ei River Dam hydro electric generating plant]]
[[Image:Breadfruit Tree 1.jpg|thumb|Mom posing in front of a breadfruit tree at Ei River Dam area]]
[[Image:C46 Crash.jpg|thumb|C46 airplane crash near Siuna to Rosita road - a passenger who survived this crash stayed at our house for a while until he was able to travel overland to Alamacamba and down the Prinzapolka river to the Caribbean coast and catch a cargo ship home to the States as he would not fly again. I wonder why?]]
[[Image:Plane Crash.jpg|thumb|View of plane crash site shortly after incident]]
[[Image:C46 Crash 2.jpg|thumb|Another photo of plane crash]]
[[Image:C46 Crash 3.jpg|thumb|Remains of C46 shortly after it crash landed in jungle after taking off from Siuna Airport]]
[[Image:My Horse.jpg|thumb|Riding my horse with friends waiting for a ride next to tennis court]]
[[Image:Hunters.jpg|thumb|Great White Hunters - Doug and I with our pellet guns]]
[[Image:Hunters 2.jpg|thumb|Great White Hunters 2 - don't ask me what the species is - looks like an alien]]
[[Image:Pistol 1.jpg|thumb|Dad doing his wild west impression]]
[[Image:Belize 1.jpg|thumb|View of Belize from the air]]
[[Image:Belize Airport.jpg|thumb|View of Belize Airport]]
[[Image:Storm DC4.jpg|thumb|Approaching rain storm at the airport - I seem to recall that we took off into it]]
[[Image:TACA DC4.jpg|thumb|One of TACA Airlines DC4's which we flew on into the storm - say your prayers]]


{{Nicaragua-geo-stub}}
No tangent line can be drawn through a point in the interior of a circle, since any such line must be a secant line. However, ''two'' tangent lines can be drawn to a circle from a point '''P''' outside of the circle. The geometrical figure of circle and both tangent lines likewise have a reflection symmetry about the radial axis joining '''P''' to the center point '''O''' of the circle. Thus length of the segments from '''P''' to the two tangent points are equal. By the [[secant-tangent theorem]], the square of this tangent length equals the [[power of a point|power of the point P]] in the circle ''C''. This power equals the product of distances from '''P''' to any two intersection points of the circle with a secant line passing through '''P'''.
{{coord|13|44|N|84|46|W|region:NI_type:city|display=title}}


{{Región Autónoma del Atlántico Norte Department}}
The tangent line ''t'' and the tangent point '''T''' have a conjugate relationship to one another, which has been generalized into the idea of [[pole and polar|pole points and polar lines]]. The same reciprocal relation exists between a point '''P''' outside the circle and the secant line joining its two points of tangency.


[[Category:Cities, towns and villages in Nicaragua]]
===Geometrical constructions===
[[Category:Municipalities of Región Autónoma del Atlántico Norte]]


[[pl:Siuna]]
It is relatively straightforward to construct a line ''t'' tangent to a circle at a point '''T''' on the circumference of the circle. A line ''a'' is drawn from '''O''', the center of the circle, through the radial point '''T'''; the line ''t'' is the [[perpendicular]] line to ''a''. One method for constructing this perpendicular isas follows. Placing the compass point on '''T''' with the circle's radius ''r'', a second point '''G''' is identified on the radial line ''a''; thus, '''T''' is the midpoint of the line segment OG. Two intersecting circles of the same radius ''R''>''r'' are drawn, centered on '''O''' and '''G''', respectively. The line drawn through their two points of intersection is the tangent line.

[[Thales' theorem]] may be used to construct the tangent lines to a point '''P''' external to the circle ''C''. A circle is drawn centered on '''M''', the midpoint of the line segment OP, where '''O''' is again the center of the circle ''C''. The intersection points '''T'''<sub>1</sub> and '''T'''<sub>2</sub> are the tangent points for lines passing through '''P''', by the following argument. The line segments OT<sub>1</sub> and OT<sub>2</sub> are radii of the circle ''C''; since both are inscribed in a semicircle, they are perpendicular to the line segments PT<sub>1</sub> and PT<sub>2</sub>, respectively. But only a tangent line is perpendicular to the radial line. Hence, the two lines from '''P''' and passing through '''T'''<sub>1</sub> and '''T'''<sub>2</sub> are tangent to the circle ''C''.

===Tangent quadrilateral theorem and inscribed circles===

A tangent quadrilateral ABCD is a closed figure of four straight sides that are tangent to a given circle ''C''. Equivalently, the circle ''C'' is [[inscribed circle|inscribed]] in the quadrilateral ABCD. The sum of opposite sides of any such quadrilateral are equal, i.e.,

:<math>
\overline{AB} + \overline{CD} = \overline{BC} + \overline{DA}
</math>

This conclusion follows from the equality of the tangent segments from the four points of the quadrilateral. Let the tangent points be denoted as '''P''' (on segment AB), '''Q''' (on segment BC), '''R''' (on segment CD) and '''S''' (on segment DA). The the symmetric tangent segments about each point of ABCD are equal, e.g., BP=BQ=''b'', CQ=CR=''c'', DR=DS=''d'', and AS=AP=''a''.
But each side of the quadrilateral is composed of two such tangent segments

:<math>
\overline{AB} + \overline{CD} = (a+b) + (c+d) = \overline{BC} + \overline{DA} = (b+c) + (d+a)
</math>
proving the theorem. The converse is also true: a circle can be inscribed into every quadrilateral in which the lengths of opposite sides sum to the same value.

This theorem has various uses. For example, it shows immediately that no rectangle can have an inscribed circle unless it is a [[square (geometry)|square]], and that every rhombus has an inscribed circle, whereas a general [[parallelogram]] does not.

==Tangent lines to two circles==

[[Image:Dilate.gif‎ ‎|thumbnail|right|The external (above) and internal (below) [[homothetic center]]s of the two circles (red) are shown as black points.]]

For two circles, there are generally four lines that are tangent to both. For two of these, the external tangent lines, the circles fall on the same side of the line; for the two others, the internal tangent lines, the circles fall on opposite sides of the line. The external tangent lines intersect in the [[homothetic center|external homothetic center]], whereas the internal tangent lines intersect at the internal homothetic center. The internal homothetic center always lies on the line joining the centers of the two circles, in the segment between the two circles. The exterior center lies on the same line, and is closer to the center of the smaller than to the center of the larger. If the two circles have equal radius, the external tangent lines are parallel, and—at least in [[inversive geometry]]— the external homothetic center, lies at [[point at infinity|infinity]].<ref>{{cite web|url=http://whistleralley.com/tangents/tangents.htm|accessdate=2008-09-29|title=Tangent circles|publisher=Whistleralley.com|author=Paul Kunkel}}</ref>

[[Image:Inner_tangent1.PNG‎|thumbnail|Inner Tangent|350px|right|The internal tangent lines pass through the internal homothetic center.]]

===Geometrical constructions===

===Belt problem===

{{Main|Belt problem}}

The internal and external tangent lines are useful in solving the ''[[belt problem]]'', which is to calculate the length of a belt or rope needed to fit snugly over two pulleys. If the belt is considered to be a mathematical line of negligible thickness, and if both pulleys are assumed to lie in exactly the same plane, the problem devolves to summing the lengths of the relevant tangent line segments with the lengths of circular arcs subtended by the belt. If the belt is wrapped about the wheels so as to cross, the interior tangent line segments are relevant. Conversely, if the belt is wrapped exteriorly around the pulleys, the exterior tangent line segments are relevant; this case is sometimes called the ''pulley problem''.

===Illustration===
[[Image:tangent_0.PNG|thumbnail|Finding Outer Tangent|right|300px|Circle tangents]]
In general the points of tangency <font color=blue>t<sub>1</sub></font> and <font color=blue>t<sub>2</sub></font> for the four lines tangent to two circles with centers <font color=blue>x<sub>1</sub></font> and <font color=blue>x<sub>2</sub></font> and radii <font color=blue>r<sub>1</sub></font> and <font color=blue>r<sub>2</sub></font> are given by solving the simultaneous equations:<br/><br/><br />
<font size="3">
( t<sub>2</sub> - x<sub>2</sub> )( t<sub>2</sub> - t<sub>1</sub> ) = 0<br/>
( t<sub>1</sub> - x<sub>1</sub> )( t<sub>2</sub> - t<sub>1</sub> ) = 0<br/>
|( t<sub>1</sub> - x<sub>1</sub> )( t<sub>1</sub> - x<sub>1</sub> )| = r<sub>1</sub><sup>2</sup><br/>
|( t<sub>2</sub> - x<sub>2</sub> )( t<sub>2</sub> - x<sub>2</sub> )| = r<sub>2</sub><sup>2</sup>
</font>
<br/><br/><br/><br/><br/>

== Outer tangent ==
[[Image:Outer_tangent_1.PNG|thumbnail|Finding Outer Tangent|350px|right|Finding outer tangent]]
The <font color=red>'Red'</font> line joining the points <font color=blue>(x3,y3)</font> and <font color=blue>(x4,y4)</font> is the outer tangent between the two circles.Given points <font color=blue>(x1,y1) , (x2,y2)</font> the points <font color=blue>(x3,y3),(x4,y4)</font> can easily
be calculated by equating the angle theta and adding the x,y coordinates of the triangle(theta) to the original coordinates (x1,y1) as shown in the figure.
<br/><br/><br/><br/><br/><br/><br/><br/><br/>

==Tangent lines to three circles: Monge's theorem==

{{main|Monge's theorem}}

For three circles denoted by ''C''<sub>1</sub>, ''C''<sub>2</sub>, and ''C''<sub>3</sub>, there are three pairs of circles (''C''<sub>1</sub>''C''<sub>2</sub>, ''C''<sub>2</sub>''C''<sub>3</sub>, and ''C''<sub>1</sub>''C''<sub>3</sub>). Since each pair of circles has two homothetic centers, there are six homothetic centers altogether. [[Gaspard Monge]] showed in the early 19th century that these six points lie on four lines, each line having three collinear points.

==Problem of Apollonius==

{{main|Special cases of Apollonius' problem}}

Many special cases of [[problem of Apollonius|Apollonius' problem]] involve finding a circle that is tangent to one or more lines. The simplest of these is to construct circles that are tangent to three given lines (the '''LLL''' problem). To solve this problem, the center of any such circle must lie on an angle bisector of the any pair of the lines; there are two angle-bisecting lines for every intersection of two lines. The intersections of these angle bisectors give the centers of solution circles. There are four such circles in general, the inscribed circle of the triangle formed by the intersection of the three lines, and the three exscribed circles.

==Generalizations==

{{Main|Pole and polar|Lie sphere geometry}}

The concept of a tangent line to one or more circles can be generalized in several ways. First, the conjugate relationship between tangent points and tangent lines can be generalized to [[pole and polar|pole points and polar lines]], in which the pole points may be anywhere, not only on the circumference of the circle. Another generalization is to consider tangent circles, rather than tangent lines; a tangent line can be considered as a tangent circle of infinite radius. The equivalency of lines, circles and points is explored more fully in [[Lie sphere geometry]].

==References==
{{reflist|1}}

==External links==

* {{MathWorld|title=Tangent lines to one circle|urlname=CircleTangentLine}}
* {{MathWorld|title=Tangent lines to two circles|urlname=Circle-CircleTangents}}

[[Category:Circles]]

Revision as of 04:12, 11 October 2008

For Seafarers International Union of North America (SIUNA), see Seafarers International Union of North America.

Siuna is a municipality in the Región Autónoma del Atlántico Norte department of Nicaragua.

The town of Siuna was the site of a gold mine operated by several U.S. and Canadian corporations in the past. Along with Rosita and Bonanza Siuna forms the Mining Triangle of Siuna.

Ground water in the area is contaminated with arsenic and mercury from the mining.[1]

The town of the Siuna has a campus of URACCAN (Universidad de las Regiones Autónomas de la Costa Caribe Nicaragüense).

With regards to the history of Siuna going back to the 1950s: My family, which included my parents, Allen and Marjorie Drebert along with my brother Doug and myself, Jim, moved from Toronto, Canada, to Siuna in 1957 where we spent 5 years until 1961. My father worked in a capacity of managing transportation and maintenance for La Luz Mining Company. We lived on the staff zone for all of the foreign workers on the top of a hill overlooking Siuna and the mine. My brother and I attended the one room school for all of the English speaking children which taught grades one to nine. After grade nine, the children or young adults had to be sent off to boarding school which would usually be back in their home country. My brother Doug and I, have very fond memories of our time growing up in Nicaragua. The mountain climate was ideal averaging between 75 and 85 degrees F. throughout the year. Check out some of the photos taken during our stay there. By: Jim Drebert. Anyone wishing to contact me regarding this article, please feel free to e-mail myself at: jimdrebert@hotmail.com

File:Allen Drebert.jpg
My father, Allen Drebert at Rosita copper mine, who shot all of the following photos
Looking down on La Luz Gold Mine complex from staff zone pool
Another view of La Luz Gold Mine picturing the main shaft tunnel cable lift
Processing the gold ore at La Luz gold mine in Siuna
Processing gold at La Luz Gold Mine
Pouring molten gold into ingot mold at La Luz Mine
Removing slag from gold ingot
Weighing gold ingots
File:Gold Mom.jpg
Mom checking out gold bar ingots
Photo of La Luz Mines maintenance shop. My Dad, Allen Drebert, was responsible for the operation of this
Photo of mechanics in vehicle maintenance shop. Does anyone from Siuna recognize yourself?
Another photo inside vehicle maintenance shop checking out a crankshaft
Pay day at Siuna Gold Mine - just outside the main gate
Street scene in Siuna
Current powerplant in Siuna on property of former La Luz mine. As the sign shows the property is currently owned by Yamana (Toronto Canada).
La Luz Mine original Open Pit where gold was initially surface mined. This ridge started to cave in with a large landslide during our time there. This is now a lake or lagoon as pictured below.
Lagoon in the center of Siuna from La Luz mine today.
View of Lagoon in Siuna which was the initial Open Pit Mine. Photo compliments of Maria from Siuna.
File:Maria at Laguna.jpg
Maria with Lagoon in background
La Luz Mines International staff zone in Siuna.
Staff zone view of pool area and clubhouse at top of hill along with tennis court
File:Brothers in Siuna.jpg
Brothers, Jim & Doug, at our pool on La Luz Mines staff zone
File:Mom and Brothers.jpg
Mother with brothers at pool
File:Dad and Mom in pool.jpg
Dad and Mom enjoying a swim
File:Jim & Doug in Pool.jpg
Brothers enjoying a swim
File:Jim in Pool.jpg
Jim enjoying a boat ride in pool
File:Pool Mom.jpg
Mom at pool next to staff zone clubhouse and single men's living quarters
Same pool, now abandoned photo taken in September 2008.
File:Tennis Court.jpg
Mom at the tennis court located next to playground
File:Front Yard.jpg
View of Mom in our front yard with golf course in the background
File:Snake on road.jpg
Friends Terry and John, our Mother, Doug and myself, Jim, on the right checking out snake that had been run down
Another photo of snake roadkill
A drive into the Nicaraguan wilderness - notice that there is nothing around except jungle and mountains
Another drive along one of the country roads
A mule train - a popular mode of transport during these years
View of an Ox team
View of a tannery where they cure cow and horse hides
Woman washing cloths in a stream - no need for the Maytag Repair Man
Classmates in our one-room English school on staff zone
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Our baseball team preparing for a game
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My baseball team at ball park next to Siuna airport runway
La Luz baseball team at ball park next to airstrip
Shopping at a Managua market
Another view of Managua market street
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View of a volcanic crater lake in the Managua area with Lake Managua in the background
View of Lake Managua
View of Lake Managua from a vacation home we stayed in for a month
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Vacation house we stayed at just outside of Managua - note that we experienced a mild earthquake during our time there - the house was violently shaking for about 30 seconds which seemed like an eternity!
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Another photo of Managua vacation house taken from the back yard
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Dad at Managua vacation house which included the use of a 1957 Chevrolet
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Prinzipolka dock viewed from about half of the way out - note that bulk carrier is off-loading sulfur which is used for the smelting process of gold, copper and other metalic ores - it was then loaded onto semi-trailers and transported up river on a large barge to Alamacamba and finally via mountain roads to Siuna and Rosita and Bonanza mines
View of sulfur that has been off loaded from cargo ship and being stored along main pier
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Nearing the mouth of the Prinzapolka River on the Caribbean Mosquito coast
Off loading supplies from cargo ship for the mines - note that I ended up becoming a Marine Engineer when I finally grew up - maybe our tour of the cargo ship inspired me
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Doug and I at the helm of the cargo ship
Barge being motored up river on the Prinzapolka carrying trailer fulls of sulfur for Siuna and Rosita and Bonanza mines, used in smelting the ores.
Semi-trailers loaded with sulfur for smelting being off loaded in Alamikamba on the Prinzipolka River for transporting the the mines - also note yacht belonging to Mr. McGowan, president of La Luz Mines
View of Alamikamba on the Prinzapolka during the dry season - where barges of sulfur and sundry mining supplies are off loaded and trucked overland to Siuna and Rosita and Bonanza mines - note the low river level during the dry season which occurs during the winter months
Rock crusher near Alamikamba used to build and maintain all of the gravel roads
Setting up a storage tank at Alamikamba
Another view of storage tank
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Father and son at Prinzapolka dock on Caribbean coast owned by La Luz Mining Company
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Cabins on Caribbean Mosquito coast at Prinzapolka owned by La Luz Mines for the accommodation of their employees on vacation or on buisness
Doug and I getting in some extended play-time on beach at Prinzapolka near sundown
Dad teaching me the finer points of seamanship in the Caribbean
Mom and Doug enjoying the sand and surf
Another view of the beautiful mosquito coast - notice the lack of tourists
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Doug and I going down Prinzapolka River towards Caribbean via tug and barge shooting a 22
Mosquito Indian family abode along the Prinzapolka River - note their mode of transport - one dugout, aka hollowed out log
House under construction along the Prinzapolka River - no need for a building permit
Mosquito family living in Prinzapolka
Mocking bird nests in large tree along Prinzapolka River
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Mom by a large tree close to #1 golfcourse green
View of Mom on golf course hole #3 - notice the vintage pickup trucks which were all numbered on their doors
View of golf course hole #4 & #5 from the front porch of our residence
View of golf course green and fairway #5 - note that airstrip is located in valley beyond golf course
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Mom teeing off on hole number 4 on our 5 hole golf course surrounding Staff Zone
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Dad chipping to #5 green
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Jim and Doug putting on #1 green
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Jim golfing on hole #1
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Brothers on way to school
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Brothers practicing baseball on staff zone playground next to school
Ei river upstream of the hydro electric dam
Ei River Dam which supplied all of the hydro electric power for the mines and the region
Photo taken behind the dam - note the overflow during the rainy season
Ei River Dam spillway pipe supplying water to turbines
Photo of Ei River Hydro Electric Plant area
Photo of Ei River Hydro Electric Power Plant area
Ei River Dam hydro electric generating plant
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Mom posing in front of a breadfruit tree at Ei River Dam area
C46 airplane crash near Siuna to Rosita road - a passenger who survived this crash stayed at our house for a while until he was able to travel overland to Alamacamba and down the Prinzapolka river to the Caribbean coast and catch a cargo ship home to the States as he would not fly again. I wonder why?
View of plane crash site shortly after incident
Another photo of plane crash
Remains of C46 shortly after it crash landed in jungle after taking off from Siuna Airport
Riding my horse with friends waiting for a ride next to tennis court
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Great White Hunters - Doug and I with our pellet guns
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Great White Hunters 2 - don't ask me what the species is - looks like an alien
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Dad doing his wild west impression
View of Belize from the air
View of Belize Airport
Approaching rain storm at the airport - I seem to recall that we took off into it
One of TACA Airlines DC4's which we flew on into the storm - say your prayers
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13°44′N 84°46′W / 13.733°N 84.767°W / 13.733; -84.767

  1. ^ Environmental Exposure and Fingernail Analysis of Arsenic and Mercury in Children and Adults in a Nicaraguan Mining Community[1]
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