Section 6. The preceding section shall not apply to publications issued solely for the purpose of giving information in relation to the flag, or of promoting patriotism or of encouraging the study of American history, or to any newspaper, periodical, book, pamphlet, certificate, diploma, warrant, or commission of appointment to office, ornamental picture, article of jewelry, or stationery for use in correspondence, on which is printed, painted, or placed the flag of the United States not connected with any advertisement and not used for advertising purposes, or to any article of jewelry upon which is placed a representation of the arms or flag of the commonwealth not connected with any advertisement and not used for advertising purposes; but no words, figures, designs or other marks of any kind shall be placed upon the flag of the United States or of the commonwealth or representation thereof, or upon any representation of the arms of the commonwealth.