(*  Read the file as pairs of values (x,y) *)
(*  One day I will figure out how to say HERE *)

xy = ReadList [ "/Users/jburkardt/public_html/math_src/graphics_examples/lynx.txt", {Number,Number} ]

(*  Create the image *)

g1 = ListPlot [ xy, PlotJoined->True, Epilog->{PlotStyle->PointSize[0.02], Map[Point,xy]}, DisplayFunction->Identity, PlotLabel->"Lynx Population Records",
FrameLabel->{"<--- Year --->","<--- Lynx Harvest --->"},Frame->{True,True,True,True},GridLines->{Automatic,Automatic},PlotRange->{{1820.0,1940.0},{0.0,7000.0}}];

(* Display the image *)

Show [ g1 ]

(* Export the image. *)
(* I have to say HERE using a huge string *)

Export["/Users/jburkardt/public_html/math_src/graphics_examples/lynx.png", g1, "PNG" ]