In State v. Holloway, 144 Conn. 295, 130 A.2d 562 (1957), the court rejected the contention that an enhanced sentence for a third time offender, under a statute enacted in 1955 and based on convictions in 1947 and 1952, constituted a violation of the ex post facto clause. "In resolving that question, the crucial fact is that the statute does not undertake to provide punishment for any crime committed prior to the date when it went into effect. The punishment provided is for a violation of the narcotics law which occurs subsequent to the effective date of the section. The only effect that a conviction antedating the statute has is to enhance the penalty to be imposed for a violation of the narcotics law. The theory of the statute is not that a person shall be punished a second time for an earlier offense but that the principal offense for which the person is being prosecuted under the statute is made more serious by reason of its being a repetition of an earlier offense or earlier offenses." Id., 301.