A category \({\bf Cln}\) representing free
algebras of clones of operations of finite but arbitrary arities
is constructed together with an adjunction \(\lan
F,U,\eta,\epsilon\ran:{\bf Set}\ra {\bf Cln}.\) This gives rise to
an algebraic theory \({\bf T}\) over \({\bf Set}.\) A
single-sorted variety \({\mathcal V}\) of clone algebras is, then,
equationally defined inspired by the multi-sorted construction of
Taylor \cite{T73}. It is shown that the Eilenberg-Moore category
of \({\bf T}\)-algebras is isomorphic to the category
\(\vec{\mathcal V}\) corresponding to the variety \({\mathcal
V}.\)