The Commissioner of Weights and Measures, or his deputy or inspectors at his direction, shall inspect and ascertain the correctness of all weights, scales, beams, instruments or mechanical devices used by any person, firm or corporation engaged in the business of purchasing milk or cream by weight. They may, for such purpose, and in the general performance of their official duties, enter, without warrant, into any place, building or premises. Said commissioner, or his deputy or inspectors, shall seal any such weighing instrument or instruments or apparatus found to be correct, and may seize and destroy any such instrument or apparatus found to be incorrect.