diff --git a/drawing.lua b/drawing.lua
index 330af31..0566a7e 100644
--- a/drawing.lua
+++ b/drawing.lua
@@ -418,7 +418,7 @@ function Drawing.keychord_pressed(chord)
     local mx,my = Drawing.coord(love.mouse.getX()-16), Drawing.coord(love.mouse.getY()-drawing.y)
     local j = Drawing.insert_point(drawing.points, mx,my)
     table.insert(drawing.pending.vertices, j)
-  elseif chord == 'C-c' and not love.mouse.isDown('1') then
+  elseif chord == 'C-o' and not love.mouse.isDown('1') then
     Current_drawing_mode = 'circle'
   elseif love.mouse.isDown('1') and chord == 'a' and Current_drawing_mode == 'circle' then
     local drawing = Drawing.current_drawing()
@@ -428,7 +428,7 @@ function Drawing.keychord_pressed(chord)
     local center = drawing.points[drawing.pending.center]
     drawing.pending.radius = geom.dist(center.x,center.y, mx,my)
     drawing.pending.start_angle = geom.angle(center.x,center.y, mx,my)
-  elseif love.mouse.isDown('1') and chord == 'c' then
+  elseif love.mouse.isDown('1') and chord == 'o' then
     Current_drawing_mode = 'circle'
     local drawing = Drawing.current_drawing()
     if drawing.pending.mode == 'freehand' then
diff --git a/help.lua b/help.lua
index e9725b7..e2f70cf 100644
--- a/help.lua
+++ b/help.lua
@@ -29,7 +29,7 @@ function draw_help_without_mouse_pressed(drawing)
     y = y + Line_height
   end
   if Current_drawing_mode ~= 'circle' then
-    love.graphics.print("* Press 'ctrl+c' to switch to drawing circles/arcs", 16+30,y)
+    love.graphics.print("* Press 'ctrl+o' to switch to drawing circles/arcs", 16+30,y)
     y = y + Line_height
   end
   if Current_drawing_mode ~= 'polygon' then
@@ -95,7 +95,7 @@ function draw_help_with_mouse_pressed(drawing)
     y = y + Line_height
   end
   if Current_drawing_mode ~= 'circle' then
-    love.graphics.print("* Press 'c' to switch to drawing circles/arcs", 16+30,y)
+    love.graphics.print("* Press 'o' to switch to drawing circles/arcs", 16+30,y)
     y = y + Line_height
   end
   if Current_drawing_mode ~= 'polygon' then