Many of the early sewing machines were powered by a treadle mechanism. The treadle was operated by pressing down on it with a foot, or both feet, to cause a rocking movement. This movement spins a large wheel on the treadle frame, connected by a thin leather belt to a smaller driving wheels on the sewing machine.
null. adj. 1. Having no legal force; invalid: render a contract null and void.2.ull. adj. 1. Having no legal force; invalid: render a contract null and void. 2.
Microsoft Access VBA Tip: Use the NZ() NullToZero Function to Handle Null Values. Behavior of Null Values in Equations (Expressions) Any arithmetic calculation in VBA with a Null value results in a null value. If one of the values is NULL, the result is Null (blank).