diff --git a/jquery.flot.js b/jquery.flot.js
index 6468f96..2bbf4fc 100644
--- a/jquery.flot.js
+++ b/jquery.flot.js
@@ -665,25 +665,25 @@
                         }
                     }
                 }
-                
+
                 if (s.bars.show) {
                     // make sure we got room for the bar on the dancing floor
                     var delta;
-                    
+
                     switch (s.bars.align) {
-                        case 'left':
+                        case "left":
                             delta = 0;
                             break;
-                        case 'right':
+                        case "right":
                             delta = -s.bars.barWidth;
                             break;
-                        case 'center':
+                        case "center":
                             delta = -s.bars.barWidth / 2;
                             break;
                         default:
-                            throw 'Invalid bar alignment: ' + s.bars.align;
+                            throw new Error("Invalid bar alignment: " + s.bars.align);
                     }
-                    
+
                     if (s.bars.horizontal) {
                         ymin += delta;
                         ymax += delta + s.bars.barWidth;
@@ -2225,23 +2225,23 @@
             // FIXME: figure out a way to add shadows (for instance along the right edge)
             ctx.lineWidth = series.bars.lineWidth;
             ctx.strokeStyle = series.color;
-            
+
             var barLeft;
 
             switch (series.bars.align) {
-                case 'left': 
+                case "left":
                     barLeft = 0;
                     break;
-                case 'right':
+                case "right":
                     barLeft = -series.bars.barWidth;
                     break;
-                case 'center':
+                case "center":
                     barLeft = -series.bars.barWidth / 2;
                     break;
                 default:
-                    throw 'Invalid bar alignment: ' + series.bars.align;
+                    throw new Error("Invalid bar alignment: " + series.bars.align);
             }
-            
+
             var fillStyleCallback = series.bars.fill ? function (bottom, top) { return getFillStyle(series.bars, series.color, bottom, top); } : null;
             plotBars(series.datapoints, barLeft, barLeft + series.bars.barWidth, 0, fillStyleCallback, series.xaxis, series.yaxis);
             ctx.restore();