This article or the following section is not adequately provided with supporting documents ( e.g. individual evidence ). Information without sufficient evidence could be removed soon. Please help Wikipedia by researching the information and including good evidence.
If a water jet pump is used to generate a vacuum , then in the event of a sudden drop in water pressure, the remaining water still present in the pump can strike back into the evacuated reaction apparatus and thus cause a chemical reaction to fail. This is prevented by inserting a Woulfe bottle .
