(a) uses, keeps or provides false or unjust scales, weighing or measuring instruments, weights or measures; or

(b) by any means prevents, or contrives to prevent, the proper officer from taking a just and true account of, or making proper examination of, any goods or materials,

shall be guilty of an offence; and any such scales, instruments weights, measures, goods and materials in respect of which the offence was committed shall be liable to forfeiture.