July 1-3- The Battle of Gettysburg, Pennsylvania. The bloodiest battle of the Civil War dashes Robert E. Lee's hopes for a successful invasion of the North. July 4- Vicksburg, Mississippi, surrenders to the Union Army under Grant.
Method. 1  Test the pen to make sure it can tell the difference between good money and computer paper. 2  Apply spray starch to the next dollar bill in an attempt to make it read as fake. 3  After drying, test the results by re-applying the counterfeit money detector pen to both the dollar and to the computer paper.
Continue Reading About counterfeit detector pen. 1  How Stuff Works explains why counterfeit detector pens are an effective tool. 2  The Secret Service is working with the computer industry to develop electronic markers that would trace counterfeit bills to the printers that made them.