Diamond v. United States

On March 31, 1939, plaintiff entered into a contract with the defendant to furnish all labor and materials required for certain betterments at the United States Assay Office in New York City. A part of the work called for in the contract was *433the cleaning of stains from the exterior stonework of the building1.

Paragraph 9 of the specifications provided a method for cleaning the stone. In this method phosphoric acid was to be used but it was found that this was not satisfactory. Experiments were conducted and plaintiff was allowed, at no additional cost to defendant, to use a solution of…