1911 Colo. Sess. Laws 408
Section 3. Every individual, firm or corporation engaged, within this commonwealth, in the- retail sale, rental or exchange of firearms, pistols or revolvers, shall keep a record of each pistol or revolver sold, rented or exchanged at retail. Said record shall be made at the time of the transaction in a book kept for that purpose and shall include the name of the person to whom the pistol or revolver is sold or rented, or with whom exchanged; his age, occupation, residence, and., if residing in a city, the street and number therein where he resides; the make, calibre and finish of said pistol, or revolver, together with its number and serial letter, if any; the date of the sale, rental or exchange of said revolver; and the name of the employee or other person making such sale, rental or exchange. Said record- book shall be open at all times to the inspection of any duly authorized police officer.
Section 4. Every individual, firm or corporation fail- ng to keep the record provided for in the first section of this act, or who shall refuse to exhibit such record when requested by a police officer, and any purchaser, lessee or exchanger of a pistol or revolver, who shall, in connection with the making of such record, give false information, shall be guilty of a Misdemeanor, and shall, upon conviction, be punished by a fine of not less than twenty-five, nor more than one hundred dollars, or by imprisonment in the county jail for a term not exceeding one year, or by both such fine and imprisonment.