Beat egg yolks until thick, add 1/2 cup sugar to eggs slowly while beating, add salt then lime juice, beat well. Cook in double boiler about ten minutes or until mixture is thick. Remove cooked mixture to mixing bowl, and add gelatin, beat for about 5 minutes. Set aside to cool.
Beat egg whites very stiff, add sugar and beat until you have a satin smooth consistency. With wooden fork beat in egg whites to cooked mixture, until all is well blended, and there are no lumps of egg white. Pour into baked 9 inch pie shell, or use graham cracker shell and either freeze for future use, or chill in refrigerator.