Thoroughly squeeze 2 quarters (half) fresh lime juice and put aside. Muddle the squeezed lime skin(s) in base of shaker until moderately bruised. Add 1.5 shots gin, 1 shot vermouth, 3/4 shot squeezed lime juice, 1 shot sugar syrup.Add ice and shake well and strain into wide martini glass. Top with soda water. Serve with ice cube and garnish with lime rind twist.