Hydraulic demonstration model for money in circulation - price rise is represented by increased level in revolving drum representing money circulating

摘要

Instrument for demonstrating effects as caused by release or decrease in money supplies, and rate of circulation of money, or the number of times than a monetary unit changes hands over a given period, using a rotating drum with a controllable inlet and outlet for a liquid, which can be set in motion to revolve at a controlled speed, and means to determine the liquid level in the drum. The liquid in the drum is taken to represent the money in circulation, with the inlet and outlet control cocks representing the corresponding monetary supply controls. Adjustment of the speed of rotation of the drum changes the circumferential speed of the liquid in the drum, causing a rise in the level at the circumference which represents the increase in prices resulting from the increased rate of circulation of the money. The drum rotates about a vertical shaft, driven by a motor with a continuously variable coupling at a measured rate. Three inlet valves and flow-meters are fitted to three inlet pipes and three similar outlet controls are fitted. The drum is made of transparent material so that the level of liquid at the circumference can be directly read off on a scale. The three inlets represent additional money put into circulation by the government excess of balance of payments and credits granted.