In Pennsylvania no customs have the force of law but those which prevail throughout the state. A custom derives its force from the tacit consent of the legislature and the people, and supposes an original, actual deed or agreement. It follows therefore, there can be no custom in relation to a matter regulated by law. Law cannot be established or abrogated except by the sovereign will, but this will may be express or implied and presumed and whether it manifests itself by word or by a series of facts is of little importance. When a custom is public, peaceable, uniform, general, continued, reasonable and certain, and has lasted 'time whereof the memory of man runneth not to the contrary,' it acquires the force of law.
Customs are general or particular customs.
By general customs is meant the common law itself, by which proceedings and determinations in courts are guided. Particular customs are those which affect the inhabitants of some particular districts only.