#### SAMUEL M. PLUMLEY v. THE UNITED STATES.

[43 C. Cls. R., 266; 45 C. Cls. R., 185; 226 U. S. R., 545.]

*On loth parties’ appeal.*

McLaughlin & Co. contract to build the Naval Observatory (37 C. Cls. R., 150). They also contract to do certain additional work for $900. The first contract is abandoned by the contractors and declared forfeited by the defendants. The second contract is performed and the work paid for. The present claimant then contracts to carry forward the unfinished construction as required by the McLaughlin contract and “ *all authorized, changes*therein.” The defendants’ architect insists that a new system of ventilation not specified in McLaughlin’s first contract constitutes a part of the work covered by the $900 contract and is unfinished work which the claimant has agreed to do. This work is of unusual character, which has never before been done by any person. It is not in any manner described in the McLaughlin specifications or contracts; and such specifications would not be understood to cover such work by a competent architect . or builder. Nevertheless the Secretary of the Navy sustains the architect and requires the claimant to do the work without compensation as being unfinished work under the $900 contract. The value of this additional work is $1,500. The claimant is also required by the architect to do other additional work not required by the McLaughlin contracts, but he does not appeal to the Secretary of the Navy. It was known to the claimant when he bid for the work that McLaughlin *&*Co. had been ordered by the architect to install the new system of ventilation and that they had begun the work when their contract was forfeited. No supplemental contract, however, had been made by McLaughlin & Co.; neither had the Secretary nor any officer ruled that such work was included in any contract.

The court below decides:

I. Where a contractor agrees to carry forward the unfinished work of a previous contractor “ *and all authorized, changes therein,”*and his agreement provides that all disputes between the architect and the contractor shall be submitted to the Secretary of the Navy, the Secretary’s decision that a new system of ventilation was unfinished work of the previous *503contractor, and that tlie present contractor can not be paid therefor, will be conclusive, though the court now finds that the new system was not embraced in the previous contract and was not an authorized change thereunder.

II. Where a contract provides that all disputes between the contractor and the architect shall be submitted to the Secretary of the Navy, whose decision thereon shall be final, the contractor can not recover for additional work which the archi- . tect compelled him to do if he did not submit the matter to the Secretary.

III. Where a contract requires the contractor to carry forward the unfinished construction of previous contractors as provided by the terms of their contract, and he knows that drawings for a new system of ventilation had been handed to the first contractors with instructions by the architect to proceed in accordance therewith, and that they had begun work in accordance with the instructions when their contract was forfeited, he will be estopped from saying that the new system was not required by the first contract or described in the specifications, unless he give notice at the time of executing the contract that he does not consider the additional work as embraced therein.

The decision of the court below is affirmed on the same ground except as to the allowance made claimant for delay by defendants, which is reversed.

January 6, 1913.

Mr. Justice Lamar

delivered the opinion of the Supreme Court