Nonlinear systems of chemical reactions are known to exhibit many different forms of behavior, including oscillations, bistability, and chaos.  The Belousov-Zhabotinsky (BZ) reaction is the most studied chemical oscillator, and generally consists of bromate ion, malonic acid, and a metal ion catalyst (usually cerium) in sulfuric acid.  By removing both the organic acid and metal ion catalyst, we were able to achieve a system that gave regular oscillations in Pt electrode potential with a period of about 1 min and a maximum amplitude of 35-40 mV.  Recently, however, it was discovered that these oscillations were initiated by fluctuations in the stirring rate caused by a periodic drop in line voltage due to the heater in a circulating water bath.  A 100 rpm drop in the stirring rate (from about 500 rpm initially) accounted for the observed drop in the measured potential.  We will discuss the difficult process of examining the entire experimental setup and eventually discovering the source of the oscillations.  Since linear systems generally should not be susceptible to stirring rate effects, this study provides evidence that the bromate-sulfuric acid system is nonlinear.  Subsequently, after the stirring effect was eliminated, this system was found to oscillate with the addition of bromide, resulting in a batch oscillator consisting only of BrO₃^-, Br^-, and H₂SO₄.