The Gin Fizz is a gin sour with a deadline: shaken ice-cold, strained into a small chilled glass with no ice, topped with soda, and meant to be drunk while it's still arguing with itself. The fizz family ruled American saloons from the 1870s on — ordered by the round at breakfast hours, built fast and drunk faster. Its most famous child, the Ramos, gets the poetry; the straight Gin Fizz is the workhorse original.
A fizz is a sour in a hurry — no ice in the glass, no time on the clock.
History
The fizz shows up in print in the 1876 edition of Jerry Thomas's Bar-Tender's Guide (as the "fiz"), and by the 1880s–90s it was a national institution, with New Orleans as its spiritual capital. No single inventor is documented — the fizz is a technique that many hands arrived at once soda water became a bar staple. The genre's rules: shaken, served up in a small glass without ice, carbonated at the last second.
Add an egg white and it's a Silver Fizz; a yolk, a Golden Fizz; cream and orange-flower water and twelve minutes of shaking, and you've wandered into Ramos territory.
The Spec
Standard sour proportions, shaken hard so the drink arrives properly cold despite the ice-free glass, with two ounces of chilled soda for the lift. The glass matters less than its temperature.
No Ice in the Glass
This is the line between a fizz and a Tom Collins: the Collins lounges over ice in a tall glass, the fizz sprints, undiluted and effervescent, in a small one. Everything — glass, soda, gin — should be as cold as you can manage before assembly.
Shake Hard, Pour Fast
The shake is doing all the chilling this drink will ever get. Go a full 15 seconds, strain, top with the soda water, and serve immediately — a fizz that sits five minutes is a glass of regret.
Bottom Line
The Gin Fizz is the most refreshing sixty seconds in the classic canon, provided you respect its one rule: speed. Make it cold, drink it young.