diff --git a/bitmap_image.hpp b/bitmap_image.hpp
index ee73501..ab0eeea 100644
--- a/bitmap_image.hpp
+++ b/bitmap_image.hpp
@@ -2195,7 +2195,7 @@ class image_drawer
       plot_pen_pixel(x2,y2);
    }
 
-   void horiztonal_line_segment(int x1, int x2, int y)
+   void horizontal_line_segment(int x1, int x2, int y)
    {
       if (x1 > x2)
       {
@@ -2208,6 +2208,11 @@ class image_drawer
       }
    }
 
+   void horiztonal_line_segment(int x1, int x2, int y)
+   {
+      horizontal_line_segment(x1, x2, y);
+   }
+
    void vertical_line_segment(int y1, int y2, int x)
    {
       if (y1 > y2)
@@ -2461,7 +2466,7 @@ class cartesian_canvas
       }
    }
 
-   void horiztonal_line_segment(double x1, double x2, double y)
+   void horizontal_line_segment(double x1, double x2, double y)
    {
       x1 = clamp_x(x1);
       x2 = clamp_x(x2);
@@ -2471,7 +2476,12 @@ class cartesian_canvas
       const int sc_x2 = static_cast<int>(cart_to_screen_x(x2));
       const int sc_y  = static_cast<int>(cart_to_screen_y(y ));
 
-      draw_.horiztonal_line_segment(sc_x1, sc_x2, sc_y);
+      draw_.horizontal_line_segment(sc_x1, sc_x2, sc_y);
+   }
+
+   void horiztonal_line_segment(double x1, double x2, double y)
+   {
+      horizontal_line_segment(x1, x2, y);
    }
 
    void vertical_line_segment(double y1, double y2, double x)
@@ -2564,7 +2574,7 @@ class cartesian_canvas
 
             for (double y = p0.second; y <= p1.second; y += 0.5)
             {
-               canvas.horiztonal_line_segment(x0, x1, y);
+               canvas.horizontal_line_segment(x0, x1, y);
 
                x0 += m0;
                x1 += m1;
@@ -2581,7 +2591,7 @@ class cartesian_canvas
 
             for (double y = p2.second; y >= p0.second; y -= 0.5)
             {
-               canvas.horiztonal_line_segment(x0, x1, y);
+               canvas.horizontal_line_segment(x0, x1, y);
 
                x0 -= m0;
                x1 -= m1;
@@ -2628,14 +2638,14 @@ class cartesian_canvas
       {
          for (double i = cx - x; i <= cx + x; i += delta)
          {
-            horiztonal_line_segment(cx - x, cx + x, cy + y);
-            horiztonal_line_segment(cx - x, cx + x, cy - y);
+            horizontal_line_segment(cx - x, cx + x, cy + y);
+            horizontal_line_segment(cx - x, cx + x, cy - y);
          }
 
          for (double i = cx - y; i <= cx + y; i += delta)
          {
-            horiztonal_line_segment(cx - y, cx + y, cy + x);
-            horiztonal_line_segment(cx - y, cx + y, cy - x);
+            horizontal_line_segment(cx - y, cx + y, cy + x);
+            horizontal_line_segment(cx - y, cx + y, cy - x);
          }
 
          y += delta;
diff --git a/bitmap_test.cpp b/bitmap_test.cpp
index b356df3..3453c4b 100644
--- a/bitmap_test.cpp
+++ b/bitmap_test.cpp
@@ -530,7 +530,7 @@ void test19()
 
       canvas.rectangle(canvas.min_x(), canvas.min_y(), canvas.max_x(), canvas.max_y());
 
-      canvas.horiztonal_line_segment(canvas.min_x(), canvas.max_x(), -400.0);
+      canvas.horizontal_line_segment(canvas.min_x(), canvas.max_x(), -400.0);
 
       canvas.line_segment(-500.0, 600.0, 600.0, -500.0);