Bell And Vaccum Sound Jar Glass
This Bell jar is for use in only Physics Experiments to teach Science. It can withstand small amounts of Vacuum. To demonstrate the principle that sound does not travel in vacuum. This is a modified unit which does not require external power source for the bell. Comes complete with Bell Jar, Bell which requires 2 AA batteries (not included), Vacuum Pump Plate, Flat Rubber Gasket, and Vacuum Hose. Assembled unit is 8.5 in. x 11.5 in. Diameter x Height.To give additional strength to the bottom edge of the Bell Jar, so as to make it resistant to chips and breaks, an additional piece of glass ring has been glued / fused to the bottom.
This is not a defect and will not affect the working of the bell jar in the sound experiments. If you receive a Bell Jar and find these air bubbles there is nothing to worry about. We do not consider these air bubbles to be a cause for return or replacing the product. Perfect for isolating experiments from outside interference or studying the Properties of Matter in a Vacuum.