This venerable classic is worth revisiting. There's a reason that your grandfather enjoyed these! And with judicious selection of whiskey and a little elbow-grease for the egg-white, you're rewarded with something very different from most of today's cocktails. 

As indicated by the name, it should be tart, with just enough sweetness to take the edge off the citrus. For best results, use a sweeter, full-flavored Bourbon whiskey.