The statutory definition of the term ``sale'' or ``sell'' is quoted in Sec. 779.15. As long as the employee in any way participates in the sale of the goods he will be considered to be ``selling'' the goods, whether he physically handles them or not. Thus, if the employee performs any work that, in a practical sense is an essential part of consummating the ``sale'' of the particular goods, he will be considered to be ``selling'' the goods. ``Selling'' goods, under section 3(s) has reference only to goods which ``have been moved in or produced for commerce by any person,'' as discussed in Sec. Sec. 779.242 and 779.243.