We construct the string field Hamiltonian for $c=1-\frac{6}{m(m+1)}$ string theory in the temporal gauge. In order to do so, we first examine the Schwinger-Dyson equations of the matrix chain models and propose the continuum version of them. Results of boundary conformal field theory are useful in making a connection between the discrete and continuum pictures. The $W$ constraints are derived from the continuum Schwinger-Dyson equations. We also check that these equations are consistent with other known results about noncritical string theory. The string field Hamiltonian is easily obtained from the continuum Schwinger-Dyson equations. It looks similar to Kaku-Kikkawa's Hamiltonian and may readily be generalized to $c>1$ cases.

24 pages+8 figures, KEK-TH-402, EPHOU-94-003