Whereas the US approached the conference solely from a technical perspective, Penney was specifically instructed by Macmillan to attempt to achieve a political agreement. This difference in approach was reflected in the broader composition of the US and UK teams. US experts were primarily drawn from academia and industry. Fisk was a vice president at Bell Telephone Laboratories and was joined by Robert Bacher and Ernest Lawrence, both physicists who had worked on the Manhattan Project. Conversely, British delegates largely held government positions. The Soviet delegation was composed primarily of academics, though virtually all of them had some link to the Soviet government. The Soviets shared the British goal of achieving an agreement at the conference. At particular issue was the ability of sensors to differentiate an underground test from an earthquake. There were four techniques examined: measurement of acoustic waves, seismic signals, radio waves, and inspection of radioactive debris. The Soviet delegation expressed confidence in each method, while Western experts argued that a more comprehensive compliance system would be necessary. The Conference of Experts was characterized as "highly professional" and productive. By the end of August 1958, the experts devised an extensive control program, known as the "Geneva System," involving 160–170 land-based monitoring posts, plus 10 additional sea-based monitors and occasional flights over land following a suspicious event (with the inspection plane being provided and controlled by the state under inspection). The experts determined that such a scheme would be able to detect 90% of underground detonations, accurate to 5 kilotons, and atmospheric tests with a minimum yield of 1 kiloton. The US had initially advocated for 650 posts, versus a Soviet proposal of 100–110. The final recommendation was a compromise forged by the British delegation. In a widely publicized and well-received communiqué dated 21 August 1958, the conference declared that it "reached the conclusion that it is technically feasible to set up ... a workable and effective control system for the detection of violations of a possible agreement on the worldwide cessation of nuclear weapons tests." The technical findings, released on 30 August 1958 in a report drafted by the Soviet delegation, were endorsed by the US and UK, which proposed that they serve as the basis for test-ban and international-control negotiations. However, the experts' report failed to address precisely who would do the monitoring and when on-site inspections—a US demand and Soviet concern—would be permitted. The experts