The colonies suffered a constant shortage of currency with which to conduct trade. There were no gold or silver mines and currency could only be obtained through trade as regulated by Great Britain. Many of the colonies felt no alternative to printing their own paper money in the form of Bills of Credit. But because there were no common regulations and in fact no standard value on which to base the notes, confusion ensued. The notes were issued by land banks, or loan offices, which based the value of mortgaged land. Some notes paid interest, others did not, some could be used only for purchase and not to repay debt. Some were issued only for public debts and could not be used in private transactions. There was no standard value common to all of the colonies. British merchant-creditors were very uncomfortable with this system, not only because of the obvious complexity, but because of the rapid depreciation of the notes due to regular fluctuations in the colonial economy. On September 1, 1764, Parliament passed the Currency Act, effectively assuming control of the colonial currency system. The act prohibited the issue of any new bills and the reissue of existing currency. Parliament favored a "hard currency" system based on the pound sterling, but was not inclined to regulate the colonial bills. Rather, they simply abolished them. The colonies protested vehemently against this. They suffered a trade deficit with Great Britain to begin with and argued that the shortage of hard capital would further exacerbate the situation. Another provision of the Currency Act established what amounted to a "superior" Vice-admiralty court, at the call of Navel [sic] commanders who wished to assure that persons suspected of smuggling or other violations of the customs laws would receive a hearing favorable to the British, and not the colonial, interests.