Goldschlager first established that a special case of the monotone pla
nar circuit problem can be solved by a Turing machine in O(log(2)n) sp
ace. Subsequently, Dymond and Cook refined the argument and proved tha
t the same class can be evaluated in O(log(2)n) time with a polynomial
number of processors. In this paper, we prove that the general monoto
ne planar circuit value problem can be evaluated in O (log(4)n) time w
ith a polynomial number of processors, settling an open problem posed
by Goldschlager and Parberry.