When such an agreement has been made between two departments, the heads thereof shall, from time to time, certify to the Director of the Division of Budget and Accounting the sum or sums due from the one to the other on account of such work, and the director shall thereupon cause to be paid such sum or sums to the creditor department. Payment may be by check, as other State bills are paid, or by a system of debits and credits, as the director may determine. All sums so received by or credited to any department shall be added to the current appropriation made for the support of said department, to the end that its appropriation may not be depleted by reason of the work done for another department.
N.J.S. § 52:14-3