Section 36. Sections thirty, thirty-one and thirty-four shall not apply to the preparation, printing, shipment and delivery of ballots to be used at a caucus, primary, state, city or town election, and said sections and sections forty-eight and fifty-six shall not apply during the sessions of the general court to persons employed in legislative printing or binding; nor shall said sections thirty, thirty-one and thirty-four apply to persons employed in any state, county or municipal institution, on a farm, or in the care of the grounds, in the stable, in the domestic or kitchen and dining room service or in store rooms or offices, or to persons employed by the commissioners of the Massachusetts maritime academy, on boats maintained by the state police for the enforcement of certain laws in the waters of the commonwealth, or in connection with the care and maintenance of state armories, or to the purchase, operation or lease of farm machinery by the department of agriculture.