The blinker is an old cocktail, tracing its roots back at least as far as its first publication in 1934 in the official mixers manual by patrick gavin duffy. The original recipe featured grenadine, and wasnt much to write home about, which may explain why the recipe languished in obscurity for so long. Dr. Cocktail ted haigh, to muggles remixed that boring old recipe, switching the grenadine for raspberry syrup and tinkering the proportions until it was just right, perfectly suited to the modern palate. Dr. Cocktail specifies that it ought to be made with white grapefruit juice, which is more bitter and less sweet than pink or red varieties, but harder to get in many parts of the world. If all you have is pink grapefruit, we promise you that it will still be delicious; however, you may want to make your raspberry syrup a scant measure.